I'm not sure if I am wrong

Angela • Twenties, engaged to the love of my life, yoga teacher, student, & student teacher 🕉❤️✌🏻☮
So I am looking for a little advice, but please be kind. My best friend and I had a giant fight. We are in our twenties and haven't had a fight in 4 years. The fight was because a girl who makes me very uncomfortable was invited to her boyfriends birthday and I said to my boyfriend I might not be able to go. The anxiety I get around her is pretty extreme. My boyfriend typed we aren't coming if she's there on my phone and accidentally hit send. I immediately said that my boyfriend sent that by accident but he's probably right and I'd do my best to come. She told her boyfriend we weren't coming and he is very hurt. She got mad at me for hurting him and brought up things I did years ago that hurt her that I apologized at the time for. She kept sending me texts even though I was not replying because she kept saying I'll talk to you later I need to calm down, before sending more texts. Finally I replied that I wasn't going to fight with her because it wasn't worth the aggravation or the friendship, and I really needed some space so to let me know if she needed me, but otherwise to give me a day or two of space. She replied it's my world and everyone else is just living in it. That really hurt because I usually give everyone their way and try to do the right thing and when I don't I worry a lot about how I affected another human. Am I wrong to say I might need to take care of myself and not put myself in a potentially terrible situation? She hurt her bf by telling him before I'd even given it any chance to think. A lot of other stupid little things happened, but based on this little bit if anyone can tell me if I really am being terribly selfish or if she's taking this a bit far? 
The girl who makes me uncomfortable btw tried to break my boyfriend and I up with a lie because her friend was interested in him. It gets much more complicated, but basically this is not a petty "you can't sit with me" type thing. She then started dating one of our close friends and the girl who liked my man dated my boyfriends closest friend at the time, affectively straining/ruining those friendships.