Aita For Not Comforting My Friend When She Was Crying?

I really wish I was making this up, but here we go. I have been friends with my group for a year and a half, but it feels like we've known each other forever. Anyway, recently, one of them, let's call her 'Amy' started treating me really crappy. Talking behind my back to mutual friends, I'll call them Sophie and Sarah. Amy makes really rude jokes to me, about my physical appearance, about some guy who has a crush on me, calls me an extremely annoying nickname, and overall just acts like a toddler. I told Sophie and Sarah about this, and they told me that Amy had been talking behind my back to them. A week ago, I had a few friends over for a party, and Amy said some really messed up things to me, basically calling me ugly. Another friend, Rachel, told me about this, as it happened when I went to grab something. I decided that I wanted to confront Amy about this last Tuesday, and everyone had my back, so we decided to do it together. As it turned out,Amy had also made Sophie cry, and had been acting extremely possessive of Sarah. They have been friends for a lot longer. We tried to talk to Amy about this, and she said it was all jokes, and said I don't understand because I have a mental illness. This was a reference to the fact that I am on the spectrum. I was really pissed off at this point, but still didn't lose my cool. Amy then started crying about how her dad was in the hospital and that we picked a bad day to talk to her. She wasn't even letting us talk. I was still really mad, so I didn't do anything, because I knew I would make things worse. I just sat there and didn't say anything. I felt bad about it, so approached her the next day and made sure everything was okay. This happened on Wednesday. Later, I found out Rachel was mad at me over what happened. She was texting me, saying some extremely derogatory things, cussing me out and calling me an Asshole. She also told one of her friends about it, and they were cussing me out over text as well, this person also called me the N-word (Neither one of us is black). I didn't know why Rachel was so mad at me at that time, and she refused to tell me what I did. She called me a parasitic friend. I was so upset that I skipped school yesterday. Today I found out that she was mad because I didn't comfort Amy when she was crying and she thought that I made Amy cry (which I didn't), but from the way she talked to me, you'd think I murdered her mom. She treated me like absolute shit over it. You'd think I deserve to know what I did wrong, but I didn't even find out directly from her. I found out from Amy. I was able to patch things up with Amy, and she isn't mad at me anymore. I talked to all my friends about what happened, and Sophie and Sarah both think I did nothing wrong, so I'm turning to an impartial party. AITA?