Few things in life are worse than the betrayal of being cheated on by someone you love.

What would you do if your girlfriend not only cheated on you but did it with your sister, who is now having her stand as a bridesmaid in her wedding?

That is what happened to the woman in this story, so she said she wasn’t going to go to the wedding at all, and her family is upset.

Is she overreacting, or is her family in the wrong? Let’s read the whole story to decide.

AITAH for refusing to attend my sister’s wedding because her bridesmaid is my cheating ex — and she knew?

I (35F) told my sister (38F) that I won’t be attending her wedding, and now the entire family is acting like I’m the one setting fire to everything.

But honestly? I feel like I just finally woke up to the fact that my sister never actually had my back.

“CeeCee” sounds like a horrible person.

Here’s the story: I dated a woman, “CeeCee,” from age 28 to 32. It was serious. I loved her deeply, saw a future with her, and was absolutely shattered when I found out she cheated — not once, but multiple times.

It wasn’t even just physical. There were messages, whole secret relationships, gaslighting, manipulation — the full narcissist starter pack.

When I confronted her, she said I was “emotionally unavailable” and she “had needs.”

I was a mess.

Her sister was there for her.

My sister was the one person I leaned on during that breakup. She said CeeCee was “toxic,” “a user,” and even called her a “sociopath.”

I truly thought she understood how badly I was hurt.

What? Why on Earth would his sister do this?

Fast forward to last month: My sister sends me her final wedding party list and there it is — CeeCee. As a bridesmaid. My ex. In her wedding party. Standing beside her on the biggest day of her life like nothing happened.

When I confronted her, she was weirdly calm. Said she and CeeCee “reconnected” through a mutual friend, and that CeeCee had “grown a lot” and was “really fun now.” She told me I was overreacting and needed to “let the past go.”

Good for her, way to stand up for yourself!

I told her if my abuser was going to be standing beside her in matching pastel dresses, I wasn’t going to be anywhere near that altar.

Then came the part that broke me: She got defensive and snapped, “It’s not like you two were even exclusive the whole time. And she and I had a moment once — get over it.”

I swear the room went silent.

Wow, her sister is just as bad as CeeCee.

Yeah. You read that right. She admitted that she hooked up with my ex while we were still together. Claimed it was “a one-time mistake” and “not emotional,” but also said I was “too busy being the victim” to realize that maybe I didn’t have the perfect relationship I thought I did.

I was shaking.

I asked her if the whole “reconnecting” thing was just a cover for them seeing each other again, and she smiled. SMILED.

Said I was being paranoid, but never actually denied it.

I wouldn’t attend either.

So I told her she could enjoy her wedding with the people who clearly matter more to her than her own sister. I wouldn’t be attending.

Now? The family group chat is blowing up. I’m being called dramatic, cold, “unforgiving.” A cousin even said, “It’s just one day, you should be happy for her.”

I’ve been called a lot of things this week. But no one’s asked me if I’m okay.

Standing up for yourself is never wrong.

So — AITAH for refusing to go to my sister’s wedding after she made my cheating ex her bridesmaid, then admitted she slept with her behind my back?

Because honestly, I feel like I’ve been set up this whole time.

AITA?

Her ex and her sister are way out of line here, and she should cut them off entirely, along with anyone else in the family taking their side.

Let’s see what the people in the comments on Reddit have to say about this.

Yup, her sister is evil.

Yup, share those secrets with everyone.

Yes, this is excellent advice.

Going no contact is the best option.

I agree, tell the fiancé!

Cut them all off, this family is the worst.

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