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Original poster

To tell my brother in law that my sister is cheating ?

190 replies

Aurelie20 · 06/03/2020 19:19

I have been reading on this forum for months and now I have something I need advice on..

My sister and I are very close and always been. She is perfect ,have a perfect house , perfect children and a perfect husband... After my marriage ended I moved in with her , and since he works night shifts I spent a lot of time with him and the children during the day.

She told me about 2 weeks ago that she has been seeing a man for roughly a month and thinks about leaving her husband but wants some time with the other man to be sure. I AM SO SHOCKED! I can't believe her. She has a perfect man that loves her and does everything for her.

I am close to him and cannot at look him in the eyes now. Especially since he always talks about her. I feel like telling him because he does not deserve that. But at the same time I don't want to lose my sister. She trusts me. What would you do.

OP posts:
Fieldofgreycorn · 07/03/2020 12:38

Also reading some of these replies makes me realise you have absolutely no idea what is really going on in their relationship.

Still keep out. Move out.

user1478172746 · 07/03/2020 13:42

Not only would I never betray my sister/brother, but I would not betray ANYONE who trusted me with this probably heavy secret (besides some cynical serial cheaters maybe). Marriage is hard, divorce can be even harder and not so simple as some make it sound. Marriage does not mean that you own the other person, man or woman.

Bluntness100 · 07/03/2020 13:46

God the things people post on here. She took you in and she trusted you and you want to blow her marriage apart before she’s taken that decision.

All the “ perfect” are you envious of her, what to remove some of that perfection? Take the shine off? Because you ain’t doing this out the goodness of your heart.

Stay out of it op, karma is a complete bitch. One day she’ll bite you harder than you can take if you do this.

Bluntness100 · 07/03/2020 13:48

And I agree, get out of her house if you’re still there. You don’t belong. Your behaviour alone, not being able to look him in the eye, shows you’re just itching to do this and want him to ask what is wrong.

Honeybee85 · 07/03/2020 13:50

Don’t say anything to your brother in law. It’s not your place to do so.

You have absolutely no idea what might be going on behind closed doors in their marriage so stay out of it. If I were your sister and you did this to me, my trust in your and therefor also our relationship, would be damaged beyond repair.

Lycidas · 07/03/2020 13:54

^No way I’d rat my sister out! Especially after offering me a place to stay. Glad you’re not my sister.^

This response demonstrates precisely why your sister is manipulative as fuck. She’s given you a place to stay, you’re now indebted to her, so now she feels secure in burdening you with her affair.

Bluntness100 · 07/03/2020 13:56

The other point is, do you have proof op? Because if you tell him and you don’t she will deny it, and everyone will think you behaved terribly and distance themselves.

Even if you do have proof they may still stay together, plenty do, and still remove you from their lives.

Proof or not, telling him doesn’t guarantee she looses her “ perfect “ life as I think you’re hoping,.

All it guarantees is you’re out and none of them will ever forgive you.

Quite rightly too.

PhilCornwall1 · 07/03/2020 14:02

If I were your sister and you did this to me, my trust in your and therefor also our relationship, would be damaged beyond repair.

I think the sister is doing a good enough job at damaging her relationship with her husband, oh and any trust too.

HighNetGirth · 07/03/2020 14:05

Yep, move out. Please don’t validate or condemn your sister. If she asks for your view, try to give her considered, sensible advice.

FazakAli · 07/03/2020 14:08

Move out, get your own plane and put strong boundaries in place between you and your sister. Don't lie or cover for her and if your bil asks questions, redirect him to your sister. I don't know if I could tell my bil but I'd try to put incriminating evidence discreetely in my bils direction & hopes he joins the dots.

TheMotherofAllDilemmas · 07/03/2020 14:10

Move out, and stay out of it. If you were DSis you would be betrayed if you tell, but you are already part of this betrayal as you are lying to a good man who is, at least partially, putting a roof over your head.

Hopoindown31 · 07/03/2020 14:49

If she was your brother what would you do?

I bet a lot of the advice on here would be different if that was the case.

DeeCeeCherry · 07/03/2020 15:05

You mention 'perfect' a lot. & seem to talk to your BIL a lot too (much). Mind your own business, move on out, try to find your own 'Mr Perfect'.

Don't imagine that if you tell him they'll split up either. You just never know. Then where will you be? Nowhere near either of them I should think, you'll be an outcast.

Original poster
Aurelie20 · 07/03/2020 15:46

Hey everyone. Thank you for your answers. I have told her this morning I don't want to hear about it ( she shows me pics of them 2 together , talks about him). She broke down in tears when I said that. Told me how I am her best friend and she needs to talk about her new romance. I also told her it was not fair to her husband , and should tell him. She said I was judging her. For those saying I am in love with my bil ,no , I am so much in love with my ex husband. He is the only man I think about. I am planning to move out in about 3 weeks , but it's going to be near them... and as before I will spend lots of time at their house. I babysit for them frequently. I know I should not judge her , but I don't want to be her alibi. It's either I accept being an excuse , or she will never speak to me again.

OP posts:
itsallthedramaMickiloveit · 07/03/2020 15:50

It's fine to judge her. You should judge her. I judge her.
Her behaviour is appalling and she has no excuse. I would absolutely tell her she needs to end her marriage now.

FreshFancyFrogglette · 07/03/2020 15:53

Saraclara if anyone/you were being cheated they/you'd want to know. Put yourself in his position. I think it's wrong to keep this to yourself personally. I can't stop thinking about how I would want to know if it was me!

Happygirl79 · 07/03/2020 15:55

Find somewhere else to stay
Keep out of it
Its nothing to do with you

Tootletum · 07/03/2020 15:59

Tbh your sister sounds very childish, as if she is the only one with needs or desires. Most people do judge adultery, yes - even judges judge it as grounds for divorce, so I'm not sure why she seems to think she is entitled to behave like this and that everyone should somehow support her selfish indulgences. That's not even the worst aspect of adultery. It's the lying and secrecy that breaks relationships. Anyway it happened to me with a friend. I told her I could not hang out with her until she told her husband. We didn't see each other for a while but she did tell him, they stayed together and she said my response did make her think about what she was doing.

Freezingold · 07/03/2020 16:40

Of course you should judge her! And you, being her sister, are the best person to judge. She will listen to you and value your opinion. The fact that she cried was positive, she needs a big wake up call. She’s terribly hurting her husband, it’s not on.

That is why she was trying to confide in you. She wants your enabling, your blessing to carry on cheating. This is the worst part of cheating. And why I think it is at its heart an abusive act. To cover her own wrongs, your sister needs to demean her husband, see flaws, and normalize her own behaviour. When really she’d absolutely hate it if her husband did this to her and if roles were reversed would hate that you knew if her husband cheated.

The more you can judge and not normalize this, keep bringing it back to the impact on her husband.

Smileyaxolotl1 · 07/03/2020 16:40

Your last post proves what the more moral posters thought all along.
Your sister is a manipulative, selfish cunt. She has no shame for what she is doing to her husband and is desperate to show off about it.
She actually sounds psychotic with her complaint about you judging her. Anyone with morals judges a cheater unless there is a really clear reason such as an abusive marriage.
Get out while you can, how could you ever trust her in anyway again when you know what a self obsessed Bitch she is?

saraclara · 07/03/2020 16:48

I don't want to be her alibi. It's either I accept being an excuse , or she will never speak to me again.

No. She absolutely can't expect you to be her alibi. That involves you lying to her husband and that's entirely unreasonable of her. You are entitled to put your foot down over that. Threatening not to speak to you again if you don't lie for her over this? She must know that's entirely unfair.

CatherineOfAragonsPomegranate · 07/03/2020 17:21

Told me how I am her best friend and she needs to talk about her new romance.

Ask her what's 'romantic' about cheating? Why does she 'need' to talk about it? Being someone's best friend or family member doesn't mean they have to compromise their morals and who they are for you. Asking them to do so rather makes you not a best friend.

It's disgusting that she expects to share all the dirty details with you and expects you to listen and chime in with questions like 'how great was the sex?' or 'Where are you two going today?' and smile and joke.

Disgusting.

Tell her no thanks.

ShawshanksRedemption · 07/03/2020 18:32

I'm guessing you're usually a good natured sort, maybe a people pleaser?

Your sister is certainly taking advantage of you by saying she'll no longer speak to you if you refuse to be her alibi. You know that this is not fair or acceptable. If you agree to it, then you will feel pretty awful, because you know it isn't OK. I feel the sooner you move out and tell her that she is being wholly unfair to you (not to mention her DH and also the kids), the better you will feel.

WinterCat · 07/03/2020 18:41

I just feel worried and sorry that my sister is ruining her life for a short affair.

That’s not how you are coming across. You sound like you don’t approve and want to tell on her because her behaviour is wrong.

Maybe it won’t be a short affair. Maybe her husband finding out will be the best thing that happens to her or maybe it will be the worst. You’re the one who won’t come out of this well.

itsallthedramaMickiloveit · 07/03/2020 18:51

You sound like you don’t approve and want to tell on her because her behaviour is wrong.

You understand she is having an affair right @WinterCat?

So there is nothing wrong with your above sentence.
OP shouldn't approve. Her sister is disgusting, her behaviour is wrong and it's right to want to tell her victim.