There was a girl I was really good friends with at work and used to meet up with outside also. We had another mutual friend at work that she was very friendly with and hung out a lot . Anyways long story short they fell out and I waz caught in the middle and had to work with both.
I asked her to tell me what happened between then but she wouldn't and she just told me he'd been horrible to her for an extended period of time. For the next 3/4 months she was absolutely horrible to me multiple times, snapped at me, once insulted me on fiont of work colleague's and was really rude loads of time on teams and WhatsApp.
Whatever happened between her and the other person affected her badly and she suffered a severe bout of depression and anxiety. I tried to talk to her sbout what happened numerous tines but she refused and kept being really horrible to me and made me feel really bad about myseif.
It then came out she had an issue wuth me being fair with the other person at work and she stopped taking to me on teams. I told her on WhatsApp I was really struggling with how she treated me and she said it wasn't her and it was the other persons fault and it wasn't fair to say it to her as she was still struggling. She also said "I guess I could have told you about the whole thing but with you staying neutral in that situation it was best for the both of us not to confide in you". A few days later she blocked me. Since then she basically blanks me and has nothing to do with me. The one time I did talk to her she said she hadn't an issue with me. I'm really struggling to understand how someone can be so horrible to you for months and then so completely unaware of what they did.