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Forgiving infidelity with my sister

181 replies

Horsey22 · 07/10/2026 19:22

The relationship is over, it was 10+ years ago. I just can’t bring myself to forgive my sister, she’s never apologised and we’ve never spoken about it since. It was my husband and father to my children. Do I leave the past in the past?

OP posts:
TheBlueKoala · 07/10/2026 20:21

Horsey22 · 07/10/2026 19:58

Sorry, no they’re not together now and I found out at the time. It’s honestly something we’ve just never spoken about and carried on like nothing happened, the children were young and both marriages separated because of it. The older I’m getting the more I’m resenting her but I don’t know why

While you were in the trenches with small kids you didn't have the time to give in to luxuries like resentment. Now you do have the time and can fathom just how massively they betrayed you.

The goal is not necessarily to forgive but to let go of all past hurt. Easier said than done I know.

SereneFinch · 07/10/2026 20:23

How on earth have you never mentioned it? Did you not confront her when you found out?

Error404FucksNotFound · 07/10/2026 20:23

I would never have spoken to her again.

Jk987 · 07/10/2026 20:26

So you’ve sat down and talked it through with your sister trying to understand… and she hasn’t apologised even once?

Oldrivet · 07/10/2026 20:26

My brother cheated on his brother when they were young (about 20). They are identical twins and they barely talk to each other now at 50.
They have never really got on that well but that really ruined their relationship.

Purplecatshopaholic · 07/10/2026 20:27

Say what now? Your sister shagged your husband? Jeez. Very personal decision about how you deal with that going forward, but I certainly would never speak to either of them again. Not. A. Chance.

Happyholidays78 · 07/10/2026 20:27

I'm sorry you've been through this, the two people you probably trusted most in the world let you down & I suspect life has never been the same for you because if it. You do not have to forgive her xx

Polipocket60 · 07/10/2026 20:28

This happened on my mums side with 2 of her cousins. They did make up years later.

I could not forgive it. Are you still with DH?

Jk987 · 07/10/2026 20:29

Sorry I’ve just read your update. The reason you feel worse about it is because you’ve never spoken about it. There’s no closure, acknowledgement or apology! That’s an impossible situation!

NovaF · 07/10/2026 20:29

Horsey22 · 07/10/2026 19:58

Sorry, no they’re not together now and I found out at the time. It’s honestly something we’ve just never spoken about and carried on like nothing happened, the children were young and both marriages separated because of it. The older I’m getting the more I’m resenting her but I don’t know why

This is insane, she had sex with your husband, both your marriages fell apart and you just carried on like nothing happened? Why would you not say anything, did other family members make you feel you couldn’t? Why did you feel you could not say anything?

ThatLemonBee · 07/10/2026 20:32

Wait are you still with him ? I’m confused . If you are , why and how and why can you forgive him but not her ?

Jk987 · 07/10/2026 20:32

SereneFinch · 07/10/2026 20:23

How on earth have you never mentioned it? Did you not confront her when you found out?

Yes, what happened when it all came out? No confrontation at all?

OutwiththeOutCrowd · 07/10/2026 20:32

You have every right to still be heartbroken about this. The bond of trust between siblings is sacrosanct. If there are no signs of contrition, this is even worse. You don't have to forgive and forget but you can find a way to accept what happened and quietly decide to hold back from true closeness in your relationship with her.

GardenCovent · 07/10/2026 20:33

Do you still speak to your sister?
Of course you feel the way you feel, you are totally justified in your feelings.
I don’t think I’d want an apology, I’d just act as if she doesn’t exist and totally cut her off

Laurmolonlabe · 07/10/2026 20:34

No I think that is a permanent sticking point.

AMarkAMissionABrandAScar · 07/10/2026 20:37

Horsey22 · 07/10/2026 19:58

Sorry, no they’re not together now and I found out at the time. It’s honestly something we’ve just never spoken about and carried on like nothing happened, the children were young and both marriages separated because of it. The older I’m getting the more I’m resenting her but I don’t know why

I do. What a fucking bitch.

DearCritic · 07/10/2026 20:37

Wow! Never speak to your sister again, children’s father minimal for child related things only. I never thought I’d give that advice….! How awful, were you close before hand? Disgusting behaviour on both their parts!!

Horsey22 · 07/10/2026 20:37

DuckbilledSplatterPuff · 07/10/2026 20:19

There's the clue right there, you both didn't speak about it.. and everything carried on like nothing happened.
But something had happened, she betrayed you.
It's understandable that having young children, you decided to just get on with it, or perhaps you didn't know where to start dealing with it.

But maybe now that you are older, perhaps have a bit more time for yourself for reflection, its really bothering you that it was all swept under the carpet. Also I think we accept things when we are younger that we simply wouldn't put up with now that we are older with a bit more experience.

I think it might really help you to find someone in RL to talk to about the whole thing... if it resulted in divorce and it was never really discussed.. You are probably seeing it now from a different perspective now you are not wrapped up in the middle of it.
I notice you seem to have more anger with your sister than your DH... I suppose because one can officially divorce a partner?

At least its all in the past now.. but if it's still bothering you, it's not unreasonable to take a second look at the situation. Maybe for closure? I'm not an expert though. That's why it would be better to talk to someone, if only to get it out of your system. Best of luck x

This is so helpful thank you. I did what I did at the time to carry on, working, living, paying the bills and looking after the children. I’m not a confrontational person and my parents didn’t want to know. They were that generation of, keep calm and carry on and that was instilled in me

OP posts:
Crudd99 · 07/10/2026 20:38

Were you close to your sister or was there any sibling rivalry or anything like that?

OpenScroller · 07/10/2026 20:38

I have to say OP, that if you carried on a relationship with your sister as if nothing happened, after she had an affair with your husband then there is some serious dysfunction within your family of birth.

Were you conditioned to believe your feelings don't matter and it doesn't matter if someone hurts you?

Could you be the family scapegoat and your sister the 'golden child'?

It's quite something that you never discussed her horrific betrayal and acted as if it didn't happen although not that unusual with the above family dynamics.

Random321 · 07/10/2026 20:39

I would want to make my peace with it for me - no one else but me - as it not allow it to impact the rest of my life negatively or cause me trust issues in other aspects of my life.

But I'd never speak to her ever again under any circumstances.

In the vast majority of affairs situations, I hold the spouse more responsible than the person they had a affair with but not in this case. Your sister isn't worth having in your life.

Horsey22 · 07/10/2026 20:40

Jk987 · 07/10/2026 20:32

Yes, what happened when it all came out? No confrontation at all?

It was a family party and the children were there, they were caught by her husband, she confessed everything, he found me and declared everything and I just left and took the children home with me (I did leave the key in the door that night so that he couldn’t come back in)

OP posts:
LowlandLucky · 07/10/2026 20:40

You didn't bury it in the past, you chose not to mention it because one person can only deal with so much at the one time. Now time has passed your mind has decided it needs to deal with it. Deal with it however you choose, you are the wronged party here and if you decide to have no contact with her then that is fine, if you stay in contact that is fine too, it is all anout what you need. Nothing else matters.💐

Horsey22 · 07/10/2026 20:42

OpenScroller · 07/10/2026 20:38

I have to say OP, that if you carried on a relationship with your sister as if nothing happened, after she had an affair with your husband then there is some serious dysfunction within your family of birth.

Were you conditioned to believe your feelings don't matter and it doesn't matter if someone hurts you?

Could you be the family scapegoat and your sister the 'golden child'?

It's quite something that you never discussed her horrific betrayal and acted as if it didn't happen although not that unusual with the above family dynamics.

Gosh. This is very accurate

OP posts:
Horsey22 · 07/10/2026 20:45

My marriage is over. So is hers. I’ve not spoken to him a lot since, yes, still contact with her, over elderly parents mainly. But no, no massive fallout at the time. I wanted to be stable for the children and the close cousin bonds they had

OP posts:
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