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AIBU?

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Sister ruined Christmas with stupid affair drama - AIBU to be really stressed?

243 replies

aerisgainsborough · 09/01/2026 13:32

It’s a long one, grab a brew and a biscuit.

I’m 36, sister B is 33, sister C is 31. All married, I have 3 children, we’re close knit, live within 5 miles of each other and do stuff with each other and our parents all the time. Middle sis has always had issues with self-esteem and either hates herself or loves herself. Has always been impulsive and attention-seeking (my youngest sis and I think she may have BPD).

B’s husband is a bit of a wet lettuce and very surface-level, is a bit ignorant and only speaks to my kids to tell them off in a really patronising voice.B He has “not made his mind up” on whether or not to start a family so B is kind of stuck in limbo on that and they won’t discuss it. She tries to let on that she doesn’t want children, but it directly contradicts what’s she’s said before and she flip flops constantly. They have very few commitments, a cat and a weekly board game club, and sit playing online games all weekend and that’s about it but reckon they live busy lives.

However, B cheated on him 10-ish years ago and he forgave her, which made us all lose respect for both B and for him because she really was horrible to him. He then proposed and they’ve been married for 5 years. He struggles a lot with anxiety etc and she says she feels more like his carer, but we’ve never seen any behaviour to support this so just generally have to take her word for it.

Recently B started a new job (she changes jobs nearly every year) and has got friendly with a male co-worker who is 10 years younger and they’ve started up a fling, despite them both being married. She “left” her husband almost immediately and declared her love for him. He strung her along for weeks, saying he couldn’t leave his girlfriend yet, going through phases of constant messaging and then ghosting her. Eventually she confronted this lad and said she loves him and he’s told her he regrets it all and nothing can happen. I was sworn to secrecy during all of this and nobody else knew but me, which was horrible and during Christmas week so I spent the whole Christmas period hosting the rest of the family while B and her husband went and played happy families with his side. I’m autistic and had a very intense internal struggle with all this. I was crying, feeling sick, unable to think about anything else. I was trying to cope with everything changing, her betrayal and not being the person I thought she was, them already being split up but not telling anyone, When it finally all came out and she told everyone, they were all angry at her for putting me in that position. It’s all everyone has been able to talk about since and my mum keeps trying to get me to find things out. I’m the eldest default child who gets leaned on by everyone and I’m just so tired.

So B is now just living with her husband as housemates and helping each other set up dating profiles. She is meeting up with a 40-odd year old she met on a kink app and during a phone call he told her that he had massive hands and could choke the life out of her if he wanted to. I’m sitting there listening as she tells me she’s meeting up with him at his flat in Manchester and I am now picturing her being chopped up and dumped in a bin. I’m trying to put some distance between me and her problems because we all get a bit enmeshed at times and it’s not good for my mental health but I am worried sick that something will happen to her.

My parents fully believe that B and husband will get back together and don’t know about B being “on the apps”. I’m sick of them asking about it and just don’t know what to do about it all. Thank you, if you’ve read this far.

OP posts:
aerisgainsborough · 09/01/2026 14:19

Primaris · 09/01/2026 14:13

Don’t agree to be sworn to secrecy.
It may help to make that a condition of her telling you anything.

Even if you are a mental health professional, you are not her therapist. You cannot be a substitute therapist for her either. If she needs to talk she has other options - therapy, the confessional, pastoral supports, the Samaritans etc.

I’m being very blunt, not to be unkind, but hopefully to help define where the lines are.

I’ve been suggesting to her to get private therapy or even marriage counselling so that they can discuss things with someone who doesn’t know them. I’ve pointed her in the direction of the BACP register, Counselling Directory etc

OP posts:
Noslogans · 09/01/2026 14:18

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aerisgainsborough · 09/01/2026 14:17

ZoggyStirdust · 09/01/2026 14:15

You’re unreasonable to lose respect for Bs husband for him being cheated on. He was the victim (twice)

I lost respect for him not having some pride in himself and running in the opposite direction. He begged her to take him back even though she was in the wrong, she played mind games with him and it was very sad to watch.

OP posts:
aerisgainsborough · 09/01/2026 14:16

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I did have some occasional time alone and everything welled up and I then had to contain it all and put the happy host face on again. Not being able to face my feelings and talk and deal with it made it a lot worse.

OP posts:
ZoggyStirdust · 09/01/2026 14:15

You’re unreasonable to lose respect for Bs husband for him being cheated on. He was the victim (twice)

aerisgainsborough · 09/01/2026 14:14

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Yep. I masked while my family were around and after a really fake and horrible Facetime with B, it got too much and when my husband saw me upset when everyone had gone, I told him. He was upset that she’d put me in that position and telling him helped a lot.

OP posts:
Noslogans · 09/01/2026 14:14

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StoppingByWoodsOnAColdEvening · 09/01/2026 14:13

Icouldwriteabookonmydisastrouslife · 09/01/2026 14:08

I have no advice but I think some posters are being harsh considering you’re ND . Please have a bit of empathy for OP . My family are all ND , we don’t always see the world like other people and we can’t understand it as quickly as others.

💐 Hope you’re ok . Maybe take a step back and rebalance your brain for a bit , tell her you care but you can’t be there for her right now . You need to concentrate on your own wellbeing,

Then the OP needs to work as a matter of importance on developing extra-strong boundaries, if she has an enmeshed, oversharing family who make a meal out of any one member's activities, and being told about a sibling's affair made her cry and feel sick and unable to think about anything else throughout Christmas (despite the fact that she neither liked her sister's ex-DH nor thought it was a healthy relationship).

Whether or not she is ND has no bearing on her ability to change other people's behaviour, but may make it extra important she develops a way of removing herself from the situation if she can't cope with it.

Primaris · 09/01/2026 14:13

Don’t agree to be sworn to secrecy.
It may help to make that a condition of her telling you anything.

Even if you are a mental health professional, you are not her therapist. You cannot be a substitute therapist for her either. If she needs to talk she has other options - therapy, the confessional, pastoral supports, the Samaritans etc.

I’m being very blunt, not to be unkind, but hopefully to help define where the lines are.

Noslogans · 09/01/2026 14:12

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This has been deleted by MNHQ for breaking our Talk Guidelines.

FlapperFlamingo · 09/01/2026 14:12

You're way over-invested and over-thinking about her life. You need to back off massively. If she calls you just tell her "sorry, I don't want to know!". If she goes silent - then great because she'll leave you alone. You honestly need to develop your own friend network and probably move away from being so close to family. You all sound a bunch of drama llamas.

aerisgainsborough · 09/01/2026 14:12

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Late diagnosed autism means I mask exceptionally well.

OP posts:
Noslogans · 09/01/2026 14:12

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aerisgainsborough · 09/01/2026 14:11

Cantheowneroftheredcorsapleasemovetheircar · 09/01/2026 13:37

To answer the question - yes, you're being unreasonable to be stressed.

This is their drama. Why is it bothering you so much??

People love all sorts of lives.

As for not being the person you thought she was - you knew she was a cheater? She did it 10 years ago?

All of it, including your emotional investment in your sister's marriage, is a bit weird.

It’s the games she plays of pretending to be so principled and she criticises my parenting, pretends she has the perfect marriage, and only gets in touch when she wants something. It’s made us all realise that she hasn’t changed at all and I feel very sorry for my brother in law. Yeah he’s a bit of a wanker but nobody deserves that.

OP posts:
Noslogans · 09/01/2026 14:10

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Icouldwriteabookonmydisastrouslife · 09/01/2026 14:08

I have no advice but I think some posters are being harsh considering you’re ND . Please have a bit of empathy for OP . My family are all ND , we don’t always see the world like other people and we can’t understand it as quickly as others.

💐 Hope you’re ok . Maybe take a step back and rebalance your brain for a bit , tell her you care but you can’t be there for her right now . You need to concentrate on your own wellbeing,

CorvusPurpureus · 09/01/2026 14:08

If you were B, I'd be advising you to focus on extricating yourself from your miserable marriage (it sounds like they're doing that, & amicably, which is great). Then staying away from dating for a bit (she's obviously got appalling judgement in this area & needs to work on her self esteem, rather than throwing herself at an attached colleague barely out of his teens, followed by Mr Kinky Strangler Hands).

But...you are NOT B. She's a grown woman. She doesn't need her big sister's input into her private life. In fact, it's probably doing her no favours at all - she needs to start seeing herself as an autonomous adult, not the ditzy troublesome middle sister like she's still a teenager.

You should back right off. Tell the rest of the family you aren't getting involved & they should ask her directly if they want to know what's going on. Tell B you don't agree with some of the stuff she's doing, you'd rather not hear about it, but you're there for a coffee.

Basically - not your 🎪 not your 🐒 🐒.

aerisgainsborough · 09/01/2026 14:08

SandrenaIsMyBloodType · 09/01/2026 13:59

People who don’t understand autism often suppose that it makes you unemotional. The opposite can often be true, especially for women. Kindly, your neurodivergence means that you are particularly ill-equipped to deal with this. You probably have an over-developed sense of what is right and wrong and it is unfair of any member of your family to try to draw you into drama and secrets. It is bound to make you feel constantly anxious.

You can’t control your sister’s behaviour anymore than you can control your emotional responses to it. You can, however, protect yourself by being clear about your boundaries. Experiment to find a phrase that feels authentic to you and shut down conversations that make you anxious and are essentially about things that are nothing to do with you; something like “I just cannot talk about this any more. It really upsets me and I need you to leave me out of it”. If they don’t yet understand how your autism is linked to your anxiety then it’s about time they learned. (Eldest daughter and mum to 2 DDs with AuDHD and an autistic DH).

Thank you for seeing me. Me and two of my children have autism and you’ve described it perfectly. I am empathetic to the point of pain sometimes and I didn’t think of the social justice angle. I get taken advantage of because of it by people who need someone to listen.

OP posts:
StoppingByWoodsOnAColdEvening · 09/01/2026 14:07

aerisgainsborough · 09/01/2026 14:03

Everything I have learned about my sister’s marriage this past few weeks has been against my will. She told me all of this and even when I told her it made me uncomfortable, she insisted on “getting it off her chest” because “it was killing her”. I work in mental health and it means I get taken advantage of sometimes because I’m kind and want to help.

I’m not really keen on her lifestyle because they’ve never grown up past about 20 and I don’t want to hear about her being tired from staying up gaming online when I spent half the night on the floor next to my disabled son’s bed because his melatonin hasn’t kicked in.

So you hold up your hand and say 'I'm going to stop you there, Angela. I don't want to hear about this.' No one has you at gunpoint forcing you to listen.

aerisgainsborough · 09/01/2026 14:05

surreygirly · 09/01/2026 14:04

Mind your own business

I wish she’d let me, believe me. Got enough shit of my own.

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aerisgainsborough · 09/01/2026 14:04

WallaceinAnderland · 09/01/2026 14:00

There's way too much information in that post, most of which is completely irrelevant to what you're asking.

As pp said, it's their life, let them get on with it.

Say you're not interested in hearing about it and don't agree to secrecy.

It felt pertinent to the situation at the time of writing. Just a bit of context that probably wasn’t needed, true.

OP posts:
surreygirly · 09/01/2026 14:04

Mind your own business

aerisgainsborough · 09/01/2026 14:03

5128gap · 09/01/2026 13:58

I'm not surprised sister B had low self esteem with you and sister C constantly overlooking and judging her for every aspect of her life.
You can't on one hand complain that her 'drama' causes you intolerable stress while continuing to be invested in and have an opinion on every detail of her life, even to the fact she isn't 'busy' enough at the weekend; and consider yourself 'betrayed' because you weren't updated as to the exact state of her marriage.
If her life is stressing you, then you need to take that as a sign of your own over investment and back off a little. Find another subject to bond with your other sister over and give the family scapegoat a rest.

Everything I have learned about my sister’s marriage this past few weeks has been against my will. She told me all of this and even when I told her it made me uncomfortable, she insisted on “getting it off her chest” because “it was killing her”. I work in mental health and it means I get taken advantage of sometimes because I’m kind and want to help.

I’m not really keen on her lifestyle because they’ve never grown up past about 20 and I don’t want to hear about her being tired from staying up gaming online when I spent half the night on the floor next to my disabled son’s bed because his melatonin hasn’t kicked in.

OP posts:
WallaceinAnderland · 09/01/2026 14:00

There's way too much information in that post, most of which is completely irrelevant to what you're asking.

As pp said, it's their life, let them get on with it.

Say you're not interested in hearing about it and don't agree to secrecy.

SandrenaIsMyBloodType · 09/01/2026 13:59

People who don’t understand autism often suppose that it makes you unemotional. The opposite can often be true, especially for women. Kindly, your neurodivergence means that you are particularly ill-equipped to deal with this. You probably have an over-developed sense of what is right and wrong and it is unfair of any member of your family to try to draw you into drama and secrets. It is bound to make you feel constantly anxious.

You can’t control your sister’s behaviour anymore than you can control your emotional responses to it. You can, however, protect yourself by being clear about your boundaries. Experiment to find a phrase that feels authentic to you and shut down conversations that make you anxious and are essentially about things that are nothing to do with you; something like “I just cannot talk about this any more. It really upsets me and I need you to leave me out of it”. If they don’t yet understand how your autism is linked to your anxiety then it’s about time they learned. (Eldest daughter and mum to 2 DDs with AuDHD and an autistic DH).

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