I feel so betrayed

[Lifesdramaneverends]

Short version
I was with my first love for 14 years, we have to kids together. I broke up with him as he was a shit dad. After 2 years of being seperated I found out that my then best friend slept with my then partner while I was pregnant with our 2nd child. She kept it from me for 7 years. I would go to her house cry about how he treated me and the kids. She would comfort me. She was stay at my house, look after my kids and cradle me as I broke down because of him. All while knowing she slept with him. I just cant get my head around how someone can do that. She was my rock, my best friend.
But what is worse is that my 2 sisters are still friends with her. One of my sisters is getting married next year and has invited the then best friend to her weekend hen party. I cant spend the weekend with this woman!! She ripped my heart out and stamped on it. I have spoke to my sister telling her why I cant come as the pain still there and her response "thats your decision."
WTF!!
You betray my sisters like this you betray me.
Why does my feelings mean nothing !!

fwiw I can’t understand why they still want to be friends with this lady if you still have such strong reactions to her.

But the fact is that they do want to be friends with her, and you can’t control that. You can only control your own actions to go or not go. If you do go can you/she remain cordial? If it kicks off - and you started it - is there a risk of her seeming the victim?

Your feelings are very valid. I’m so sorry. Well done for taking a stand and not putting yourself in a potentially painful situation.

Your sister inviting this person is odd, but nothing something you can change. You can control your own reaction and dignity. Can you do something nice with you and the kids on her wedding day? Weddings are alright, but attending one isn’t as important as putting your own feelings first in this case.

OP, it the ultimate betrayal and you're understandably still hurt. I do find it bizzare that your sister would 'choose' this woman over you, but other than do what you have, I'm not sure what other options you have. Stay away from the hen party (and wedding if you have to) and take that time to do something nice for yourself.

Yanbu - I would be so hurt if my sisters did this to me! In fact, I'm v confident they wouldn't... horrible behaviour.

Your sister is being a shit sister to you by inviting this woman.
I wouldn't treat you like this if you were my sister.
And if I was your Mum I wouldn't be happy about the situation either.

However if your sister is usually nice & reasonable there are only two reasons I can think of why she is inviting your ex best friend is

1. that your sis puts all the blame on your deadbeat ex & is maybe trying to organise a reconciliation between you & your ex friend.
2. that your sis is a bit clueless & thinks that now you've got rid of your waste of space ex & it's years later that you should have put it all behind you.

If I was in your situation I would say (names completely fictitious)
"Hey sis how would you feel if you found out that Lydia your best mate had slept with your ExH Dave whilst you & him were still married?
Would you be happy if I invited Lydia to my wedding in those circumstances"

Wait & see wait your sis says.

You broke up with him as he was a terrible dad so why on earth is that not your priority you are not living in EastEnders focus on your children and act like an adult is the only advice I can think works

I would not attend the wedding either, assuming ex best friend is invited. Tell your sister it's too painful to see her, brings back bad memories, and let her know you feel she has chosen your ex friend over you. This may create more distance with your sister, but maybe that's best as she sounds like a bit of a selfish, uncaring bitch. A good sister would not do this and I'm sorry she did. Your family should have your back, that's the bare minimum you should be able to expect from them. If they don't, what good are they?
My brother chose my cheating ex over me and it was tremendously hurtful. I don't speak to him anymore, which is fine, because he's always been an asshole anyway.

What are you talking about? That makes no sense.

Your sisters are horrible and have no loyalty to you. Family is sometimes just an unfortunate circumstance of genetics. I would tell them to both fuck off. The notion that because they are family you have to have them in your life is ludicrous. You would be better off without people like this in your life. Good sisters who love you wouldn't do this to you.

@PollyBellYou are a nasty person. I think you just come on Mumsnet to be rude to people to justify your miserable existence.

OP has the right to feel hurt and upset by what’s going on, show some compassion or don’t comment.

It’s crap and it shows you you can not rely on your sister to have your back. I wouldn’t go on the hen either. I’d assume she will be invited to the wedding too so you will need to decide how you feel about that.

That’s a double betrayal.
EX best friend is the lowest form of human. It’s one thing knowingly shagging a man in a relationship - it’s another level when that man is in a relationship with your best friend.
And I think your sisters have either bumped their heads, or they actually don’t like you. My sister & I are one. Shit on one of us, you’ve shat on us both.
I can’t really advise on how I’d approach this, given my sister & I just get it, I think probably I’d confront her and give her a day to rethink and pick a side.

This is awful disloyalty on the part of yours sisters. They are putting their friendship with this woman, who was supposedly supporting you while having sex with your husband. I'd be confining them both to the bin of people I wanted as little as possible to do with and I'd be cheering myself up with thoughts of which of your sisters' husbands or partners she'll have it off with first. I mean it's not as if she shows any signs of appropriate behaviour given the adultery and hypocrisy.

Seriously you think being betrayed by your best friend having sex with your partner while you are pregnant isn't a big deal?
The betrayal by her so called friend was on a par with, if not worse, than that of her partner.

I would like to thank you all for your opinions (apart from the one who I think we all thought was very cold and why even be on here). I thought I was going crazy for feeling so hurt. I did confront my sister and she gaslighted the whole situation pulling up on past experiences which I had to choice over. She even overlooked the whole situation with my abusive ex using my vulnerability to aid her side. I am gutted that my feelings just got dismissed. I wasnt even rude I just messaged her telling her how it made me feel and that I didnt expect any change as the damage already been done. But wanted to communicate with her. She just kicked off. Saying that when I dont get my own way I always kick off. This is not what I do. Yes if I have a problem I do voice it as for years I didn't care about how I felt. I have learnt that it is not ok. So I politely speak my mind but people don't like to told the truth. I stepped so lightly as I really want to be at my little sisters hen and wedding but I dont think that is going to happen. And what is even worse is if I dont "suck it up" and go I will be the arsehole in the family. Again! My feelings seem not to matter in my family, just have to struggle in silence.

Your "d"sis is a cow and your family are shits if none of them back you up.
I feel for you, I'd take a step back.
I have three dsis, we've had fall outs, stand up knock down fights (as teenagers) arguments as adults but if anyone hurts one of us they're dead to us, we will plan their downfall over a glass of wine and a bucket of sympathy for the hurt dsis 😉
I actually say, if someone does anything to me "they're going to be sorry when my dsis's find out"
That's an example of how dsis behave.
Take care of yourself, you can't rely on them ❤️

Please don’t let her words hurt you. Don’t go to the wedding, but also don’t give her the pleasure of any drama over it. You have, rightly, voiced your views. She has chosen not to listen and use it as an opportunity to be unkind.
Protecting your own sanity if priority here. It’s fine not to go, you have a choice to put yourself first. You’ve made your views known and it will sting that you have been ignored, but the real strength here comes from you making the choice that protects you from further hurt by not attending.
Send her a card, a gift, enthuse about any wedding comments as you might naturally do, but don’t go. Plan a nice day out instead. Your feelings are valid, they matter and only you have the power to protect yourself here. 💐

ETA: if anyone is kicking off when they don’t get their way it is her. “Not getting your way” would be something like you wanting to wear blue and she not allowing it. Not putting yourself in an emotionally difficult situation is “not getting your way”. She can FO.

What do your Mum & Dad say about it?
I'm presuming that they're still around (apologies if they're not)

I'm so sorry your sister is so toxic. You are completely right to stand up for yourself. If you had just gone along to get along, that wouldn't be true to yourself and you would regret it. It sounds like she is one of those people who just can't be reasoned with. If your family doesn't value you enough to be loyal, you may have to limit your contact. I had to do that when I decided to leave my ex. I became the arsehole of the family to certain members of it and they were blaming me and defending my ex to both me and my youngest daughter. She had to stop seeing family for awhile because when she visited them my mother and brother would not stop pressuring her to forgive my emotionally abusive, cheating drunkard ex. I stopped communicating with them until I got an apology. Turned out it wasn't sincere and they were still blaming me behind my back, but I didn't find that out until after my mother died, so I never got closure about that.
So sometimes going no contact can get them to at least agree to not talk shit about you to your face. It worked on my MIL too. You could try it. I made sure to be clear about why I was not going to communicate with them and what they needed to do if they wanted to be back in my life. Then I stuck to it for about a year in both instances, and they finally caved. They must have known I was not going to give in. You have to be prepared to be stubborn as hell. Also be prepared for the possibility that your sister may not care if she is in your life. She sounds like she might not. I agree with a PP who said you should still send a wedding present and a card. Then don't contact her, wait for her to contact you, whereupon you can tell her why you wish no further communication unless she agrees to change her behaviour around you. Be specific about what behaviour needs to change. Be matter of fact and polite and absolutely do not get drawn into an argument. It's one text in which you outline your conditions and if the answer isn't yes, you ghost her. Do you think it's worth a try?