My bff(23F) of 9years and I(24F) ended our friendship recently and I can’t stop wondering if I’m in the wrong. We became friends in high school and our friendship was great up till a 3 years ago where I constantly felt like a place holder (making new friends then her bf/now fiancee) and when I did make friends it would upset her because I’m not paying attention to her as much anymore. I always let it pass because she was going through a lot. A couple of months ago my mom was battling cancer and it felt like my life was falling apart so I called her for some support because I was genuinely losing my mind, when she answered I was already bawling my eyes out but she hung up after maybe 30 seconds of answering because her fiancee was coming over that night and she couldn’t talk to me at that moment. I felt really distant after that because that’s the first time I’m 9 years where I called her and told her I needed her (I’ve been there for her through thick and thin), she called me 3 days after to show me the house her fiancee bought for them to move into after they got married and I didn’t show my usual enthusiasm so we got into an argument (she didn’t even check on me btw). Ever since our friendship was really distant and shaky, so I ended up making new friends at university and a couple of weeks after it turns out the friend group I was apart of was also her sil’s friend groups. Once I figured out I told my bff and she didn’t say much about it, every time I’d hang out with them I’ll give her a little update because again she was my bff and we had a bunch of classes together (still not nearly as close as we were before the argument). A couple of months pass by and she tells me she wants me to cut off that friend group because she didn’t think it was fair for me to be apart of her sil friend group and not her, and when I offered to introduce her she refused saying her sil should not me. I didn’t say much (because I didn’t know what to say at that moment), then she kept on saying that’s if I don’t listen to her and drop them she’ll tell her fiance to tell his sister to drop me and so would the other girls in the group (which flash forward did happen after I refused), my reasoning was I couldn’t because if I drop them out of no where ( they were popular) it’ll start problems for me and I’ll be excluded from my organization. And she said that’s fine because I’ll be graduating next year but she will be her sil forever. And if I don’t she’ll cancel my invite to her wedding. We ended the conversation there, I tried talking with her 2 times after because again she was my friend of years and I didn’t want it to end over something so dumb and it’s hard letting go of someone you were so close with at some point. She ignored me reaching out till one day I stopped her after class so we can at least talk it out. She ended up screaming at me that I am inconsiderate and it was unfair that I was in the friend group and how I knew details about her marital events that she didn’t know (her in laws were in charge of the other events). Then it led to her saying she didn’t like how I always made new friends and how I get all the attention especially now (\* I used to be overweight, I still took care of myself back then but once I lost the excess weight I became somewhat attractive, and I can be funny every now and then so people tend to enjoy my company/feel very comfortable around me). She went on with more things she held in for years apparently that had nothing to do with me more of how she perceived me. Pass forward, I was texting on of our friend and how sad I felt over the situation, and that I feel miserable about ending such a long friendship with someone I cared about. A week after those texts I was invited to a potluck and my bff was also invited, I arrived a little late because I had work that day and everyone was ignoring me. No one touched the food I bought which it usually the first thing to go, and everyone was side eyeing me speaking in their language (I’m the only one who’s not from that country so I don’t speak the language). I felt really tight chested that day but thought it was all in my head because I had a long day, till someone from the potluck took food from my dish and she whispered something to them and they returned the food to the dish. And then she was purposely showing my her screen (pointed her food indirectly towards me) and I could see my texts on her phone….They were laughing at it. I reached out to my other friend and asked if she screenshotted my text and sent it to my bff and she said kept denying it then said yes. I left the potluck. Her excuse was this all happened because I didn’t want to cut out her sil group and me reaching out to our friend and telling her I felt miserable because of the situation. I don’t think I didn’t anything wrong here but part of me can’t help but wonder if AIO because there is no way I wasn’t at fault and everyone (my bff, her sil friend group, 2 of our shared friend groups) ended up cutting me of out of nowhere. I ended up taking my rsvp away for the wedding, she texted me the night before her wedding asking if I can come, all of our friends ended up calling me nonstop too to come to the wedding so I ended up going even though I was so sick I couldn’t speak because I lost my voice. I was again completely ignored by everyone at the wedding (I have no clue why I went but it’s probably because I was so sick I couldn’t think straight, this will be one of my biggest regrets). We haven’t spoken since then but again I can’t stop thinking about it and wondering if I’m in the wrong. 

AIO for not dropping my bff sil friend group?