AITAH for still having ill feelings/anger towards one of my best friends after an incident occured

A few months ago my close friend group decided to attend the activities on school that evening since we always participate them. That evening when we went to school one of us didn't come. We were confused as to why she didn't come when she clearly told me she'll come. She didn't message anyone saying she won't come or anything so I suggested that it's most probably cause she wanted to meet her bf ( because this was the same reason she didn't attend an event a few days ago) . We all agreed and decided to ask her after coming home. Fast forward - after going home one of us messaged her asking why she didn't come. She didn't reply so my friend messaged her again saying 'it's cause you wanted to see your bf huh? We get you want to meet him but still you should have come cause we all promised. You can't bail at the last minute.' This got no reply from the best friend (that didn't come) either. After a while one of the guy friends informed us that the best friend that didn't come, her bf had threatened him and almost beat him up for making her cry. He said that the bf made death threats to us and said other stuff like I'll beat the sh*t out of the one that messaged her. After this incident I felt scared and slightly angry at the the best friend that didn't come cause why was she crying? Especially by locking herself up on the room and not talking to anyone.We literally asked her why she didn't come. We were just hurt cause she bailed on us again without a proper reason.We all did make up after a few days but I still can't seem to forgive her bf(he never apologized to us. He said he couldn't just control himself) He had no right to do that. I'm still besties with her cause I don't think she was exactly in the wrong but I still have some negetive feeling towards her and I can't even joke around her anymore as much cause I'm scared her bf might do something to me. Am I being too dramatic or not?