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AIBU?

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Original poster

My sister is having an affair

140 replies

cheatingsister · 18/09/2018 08:14

NC for this as coupled with my other posts, it could be very outing.

My DSis (25) has been with her DP (32) for 9 years. He's been in the family much longer, around 15 years, as close family friends. We spend New Years, holidays etc with them.

He is a truly lovely person - kind, hard working & treats my sister like a princess.

He's held off buying a place (is currently renting his parents annexe) until DSis is working FT & earning a steady wage.

He's supported DSis financially (as well as emotional, obviously!) through uni, post grad study. She has just secured a role in her chosen field and is due to start at the end of the month.

They are a great couple.

Around a year ago, DSis confessed to me that she was having an affair with a man from a couple they'd met on holiday. He lived around 1.5hrs away & she'd lie to her DP & say she was with friends (or staying with me!!!).
She continued to see him 2-4 times per month for around 6 months.
He ended it.

In March, she met someone else whilst on a skiing hols with her friends. Again, he lives about 1.5hrs away.
Last week, she stayed with him for 6 days, telling her DP that she was staying with me.

DM also knows - she feels awful as sees his DM (her BF) most days for a dog walk. She has started making excuses not to see her as she can't stand covering for my DSis. She's also stopped socialising with his DM & DF in the evenings ie going for a drink as her and DSF just can't lie to them.

DM, DH & I have begged, pleaded with her to either end the relationship with her DP & enjoy her self or to stop cheating.
We've tried supporting her, we've tried getting angry with her. Nothing makes a difference. She says she's ended it then will drop me a text "I'm at yours if X asks, ok?"

She left OM's yesterday, came back & DP is taking her for a v posh, expensive bday meal this evening.

It's absolutely disgraceful. I feel by us lying, we are enabling this.

I'm seriously considering telling her DP what she's up to. AIBU? And if not, how would I go about doing it??

OP posts:
longwayoff · 18/09/2018 08:19

You cant change her, none of you can. Horrible situation for everyone to know but him. Personally, I'd stick my fingers in my ears and close my eyes. Whatever you do can only make things worse. I hope someone has better advice for you, it must be very stressful.

princesstiasmum · 18/09/2018 08:21

Refuse to lie for her anymore.and tell her if her Do asks if she's with you tell him no

Whatsnewwithyou · 18/09/2018 08:21

I think the most you can do is tell her you won't lie for her. So if her DP asks if she was with you, you will honestly tell him no. Otherwise I think you need to stay out of it or risk your relationship with your sister.

Also I think that when they got together a 23 year old with a 16 year old was very unlikely to lead to a healthy stable relationship. At 16 she was a child, at 23 he wasn't. She probably sees him more as a father-figure type than a partner. Having been with an adult since the age of 16 means she has no idea how to be without a relationship with someone taking care of her. Not saying this excuses her behaviour but it makes it a little more understandable I think.

princesstiasmum · 18/09/2018 08:22

DO not do

AdoreTheBeach · 18/09/2018 08:22

OP your sister has put you and your parents in a very unfair position. While you can’t change her behaviour, you can only stop enabling her. Yourself and your parents can put a united front that you will no longer cover for her, repeat what you’ve said above - either end the other relationships or make a go of her relationship, that you find her behaviour disgraceful and you’ll no liner lie for her as it’s enabling behaviour you find disgraceful.

I’m not too sure about your telling her husband. On the fence about that but I do know if it were me and people knew, were lying to cover for the other person, I’d feel stabbed in the back.

Hugs to you OP.

BMOT · 18/09/2018 08:23

Its an awful situation to be put in but whatever you do don't be the one that tells the Boyfriends as in my experience it will end up biting you in the ass.
However if it was me I would be having strong words with my sister and telling her that though it is up to her how she chooses to live her life I am not willing to collude with her and would not be telling her boyfriend she was with me.

ShatnersWig · 18/09/2018 08:27

She's a bitch.

If there had been one short, stupid fling, I think I could keep quiet. But not now. She's taking this man for a ride, financially. And you're all prepared to sit there with him, knowing what she's doing, except your DSF. You are all complicit because you're actively involved in covering for her. She's awful, but you lot aren't much better. Turning a blind eye is one thing, but agreeing to lie for where she is so she can cheat on this guy you've all known for 15 years? Nice.

MistressDeeCee · 18/09/2018 08:27

For all you know she could end up with this other man and you won't be able to do a thing about it. She's an adult. Her being wrong and you taking it upon yourself to intervene in her marriage doesn't make you right. Tell her you won't stand for her saying she's with you when she isn't, and leave it at that.

Returnofthesmileybar · 18/09/2018 08:28

Two affairs? Your sister is a using bitch. Tell her she either tells him or you do, say your happy to deal with fall out because all this has made you realised she's only a cunt anyway. Let's be clear here, it's bad enough she is having an affair but she doesn't give a shiney shit about ye, about the position you are in, about her relationship with her mother, her mother's friendships, why are you covering for this nasty bitch? I'm not being flippant, I appreciate it's hard for you, but she clearly doesn't care about you guys

Collaborate · 18/09/2018 08:29

You could all start by telling her you'll not cover for her. If she uses you as an excuse to stay with the other man for 6 days tell her you will not lie to her partner or try and avoid him. That if your mother speaks to his mother and she asks after your sister she'll not lie and act as if she's staying at yours. When she uses you as an excuse next go out for the night and put posts on facebook showing what you're doing.

foxotterhare · 18/09/2018 08:30

I would tell her that she tells him or i do.

foxotterhare · 18/09/2018 08:32

I don't think your parents should have let her go out with an older family friend at the age of 16. Something has gone wrong here.

FurryBuzzer · 18/09/2018 08:34

Three options here, I think

  1. cover for her
  2. don't cover for her but don't volunteer information (so if he asks if she's with you, tell him she isn't but don't go out of your way to let him know)
  3. tell him, maybe with a pre-warning to give her a chance to come clean first i.e. "I think you should tell him and if you don't then I will on Saturday"

Given you all seem to know him and his family and you've already given her plenty of chances to do something then I'd be inclined towards option 3 in your situation.

I do have- sort of - some sympathy. If she's been with him since she was 16 and everyone in the family knows him and says he's a great guy, it could be hard to break out of the the relationship, even if it's no longer making her happy. But the way to do that is put her big girl pants on and be honest, not repeatedly cheat (you know this, obviously!)

Original poster
cheatingsister · 18/09/2018 08:34

I haven't actually had a conversation with him as in "is X with you?" - but it's the feeling I can't post something on FB for example.

If he asked me "is x with you?" I would have to tell the truth & say no.

I've told her I'm not covering for her anymore but until he actually asks me about her stay etc there's not much I can do.

It's so stressful. I'm so disgusted in her behaviour for it.

PP commenting that it's more of a father-daughter relationship is interesting as DM & DF split when she was 9 as he had fathered a child out of the marriage. He passed away 12 months into their relationship.

OP posts:
Tattletale · 18/09/2018 08:34

Hang on, he is only 7 years older. Let's stop with trying to paint this guy like some sort of perv when it seems he has only ever been supportive.

ShatnersWig · 18/09/2018 08:34

@foxotterhare Not sure that's at all relevant to the matter at hand. I've known many similar situations over the years, rightly or wrongly.

babswindsor · 18/09/2018 08:35

I think it's quite possible that your sister has grown out of the relationship she has had with her partner since the age of 16, lovely though he may be. It is possible that she doesn't know what to do because she knows how much everyone in her family likes him.

I think that your sister needs to be helped to leave her partner, if that's what she wants to do. Yes definitely stop covering for her, but perhaps you or your mum could ask her what's wrong, and ask her if she wants to split up. She might need your 'approval' to make the break.

SilverLining10 · 18/09/2018 08:36

Shes absolute scum. Really she is. Her dp deserves to be told. He deserves much better

MsHomeSlice · 18/09/2018 08:36

What a horrid person she is, I would refuse to lie on her behalf! Does he never ask what you were all up to? That poor man!

I would tell her no more, and that if she even dared to send me another "I am with you!" test I'd go out of my way to ensure I bumped into her dh and let him draw his own conclusions!

You KNOW she will drop you all right in it when he does work it out, "oh well EVERYBODY knows anyway" ...he is going to feel totally humiliated.

Disfordarkchocolate · 18/09/2018 08:37

I wouldn't say anything but I wouldn't lie and I wouldn't avoid him. She's put you in an aweful position.

Original poster
cheatingsister · 18/09/2018 08:37

@foxotterhare not that it makes any difference but she was v mature for her age. I think I'd much prefer my DD to be in a relationship with someone we all knew, respected & loved as opposed to the sort of guys I went out with at that age!

OP posts:
MsHomeSlice · 18/09/2018 08:37

text** not test.

nellieellie · 18/09/2018 08:37

I wouldn’t cover for her, so I’d make it quite clear that if the question arose, No, I wouldn’t say she was with me. These people are family friends. She has effectively ruined the relationship between your DM and her friends. That’s horrid. She should at least have the decency to keep it to herself and not try to involve her family in duplicity. I’d be totally upfront and say that you do not want her to ever talk to you about her affairs ever again. You do not want to know.

babswindsor · 18/09/2018 08:38

Yes but this isn't about you, cheating sister, it is about her. I think she feels trapped.

Original poster
cheatingsister · 18/09/2018 08:40

It's not a case of bumping into him either - DH & I live 2.5hrs away. If I was in DMs position I certainly wouldn't have been able to control my mouth.

We've given her so much support but she maintains she doesn't want to leave him. We've assured her that people change, people fall in & out of love. Honestly, we couldnt have been more supportive for her to leave... but she simply won't.

The OM sounds like a complete tramp so I very much doubt she actually has fallen in love with him & wants to be with him.

OP posts:
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