"AITA for refusing to my sister's wedding?"

I (M27) have a twin sister (F27). For as long as I can remember, my sister and I have always been close and had each other's backs. When she came out as gay, I was the first one she told. I supported her wholeheartedly. 3 years ago. I was engaged to my then girlfriend, Julie. We had met in college and became fast friends, eventually becoming a couple. I proposed to Julie and she said yes.

Everything seemed fine, until I noticed that Julie had started to be a little more distant with me. Not giving me a cold shoulder or anything, but off. I asked her if she was ok. She said she's fine, but would like some space for a while. I was worried, but I respected her wishes and gave her space. A few weeks later, she broke up with me. I was devastated and didn't know what happened.

I reached out to my sister for support and she was there for me. She and Julie had gotten along really well, so I asked her if she knew what happened. She was hesitant, but said yes. I asked to explain and she said it's not her place to tell me. I kept pushing, but my sister stood her ground and said that she can't say why and Julie will tell me when and if she's ready.

Well, she did. Turns out Julie was bisexual but thought it was just passing feelings. She'd never been with a girl before. She spoke to my sister about it, and my sister helped her realize her true sexuality and feelings. Her words. Julie told me that it wouldn't be fair to either of us if she didn't embrace her true self and the fact that she no longer had the same feelings for me she had before.

I was stunned, but eventually accepted it. We parted on good terms, even if it was awkward. I was heartbroken, but eventually moved on (didn't start dating or want to tho for a while). Then, one day, I found out Julie had started dating another girl: my sister. I was shocked and, admittedly, a bit angry at both of them. I had an arguement with my sister.

My sister swore they didn't do anything while she was with me, but Julie had admitted she had a crush on my sister. My sister liked her back, but didn't do anything because of me. She swore she didn't make Julie dump me to be with her. The sad part was, I could tell she was telling the truth. After that, my relationship with my sister wasn't as great as it used be.

I stopped talking to her as much or visiting. Fast forward to a few weeks ago, and my sister comes over alone and tells me that she and Julie are engaged, and she was here to invite me to the wedding. The rest of the conversation was a blur, but after she left, I drank. A lot. And after thinking about it for a few days, I told my sister I wouldn't be attending her wedding.

She was heartbroken and begged me to come, because she wanted me there. Even my mom called me, asking me to come. I told her no. Regardless, I refuse to go. I just can't stand having to be there in the crowd and see my sister marry the woman I had planned to marry. Idk, maybe I'm just holding a grudge. AITA?

What do you think? AITA? This is what top commenters had to say:

Punisher6111 said:

NTA. I mean your sister cross the line IMO. I would never date any of my brothers exes. Even if I had *feelings". That is a line I would never cross.

acar4aa said:

NTA. What kind of sibling goes for your ex? I feel like that’s breaking so many codes.

terayonjf said:

NTA it's bad enough she's with your ex but to know how it affected you and still asked you to come to the wedding is insane. I don't understand how she thought that interaction was going to go. In what universe were you supposed to graciously accept that invitation.

bobsbadbitch said:

NTA your sister and Julie are the arseholes. I’d refuse too and I probably would never forgive them or want anything to do with either of them it is just immoral. Don’t let your parents guilt you into it because it shows how much they are arseholes too. They should be telling your sister actually it isn’t appropriate to invite your sister after what you’ve done to her. Sending love.

Edit:

Thank you everyone for your responses. Even if I didn't respond to all of them, I have read all of them. I've decided to not attend the wedding. While part of me is still hurt, the truth of the matter is that my sister was more than just a twin, she was my best friend since birth.

And, right now, I can't bring myself to cut her off completely. For now, I'm going low contact and I'll be looking at taking a trip to Vancouver during the time of the wedding.

Two months later, he shared this update:

Hey everyone, the wedding was last weekend and, as I said in an edit, I took a trip to Vancouver. I disconnected from everyone and just enjoyed the beautiful Canadian city. Before going, I called my sister and told her that I wasn't coming. I figured I owed my twin that much. She was upset, but she surprisingly agreed with my decision. I told my parents and they told me they understood.

So, I left last Friday and came back this Monday. From what I heard, many people asked about me, but the wedding went off without a hitch. While I was there, I decided that, despite everything, I loved my sister and still wanted a relationship with her. So when I came home on Monday, I drove straight to her place.

Luckily, my ex was asleep and they weren't leaving for their honeymoon until Tuesday. I took my sister to a local cafe we loved as kids and talked. I explained to her my feelings and even showed her the post I made and all your comments. She started crying and apologizing for hurting me and being an awful twin.

She asked me if I was planning to go no contact with her. I told her no, and I didn't expect her to leave her now wife for my sake. But, I also told her to not expect me around as much. At least for now. I'm gonna start counseling, as many of you suggested.

I told her this and she started apologizing again, saying she never meant to push me this far and she would've left my ex a long time ago if I'd told her how much it bothered me. She assumed since I didn't, that I was ok with it.

I told her straight up that love works in some odd ways, and while I understand she fell in love, I couldn't have the same relationship with her as we used to. That we'd have to work on it. We ended the conversation on a tense, but also optimistic note.

When I dropped her home, she wrapped me in a hug and just held me for a long time. Then she broke apart, gave me a sad smile, and went inside. She left for her honeymoon on Tuesday and I started my counseling on Thursday, which I feel went well. Just wanna say again, thank you to everyone that commented and DM'd me after my first post.