My friend's eating disorder traumatized me

Before anyone calls me an asshole, please read this through. I know it's not her fault.

I've had many friends with eating disorders, although the issue is I've met them when they were already sick, this friend wasn't. We met in August 2024 and quickly became close after realizing we'll be in the same classes in high school. We spent nearly everyday together until about December/January. She started developing an ED around late October but I didn't realize until January. She hid it really well and always had an excuse why she couldn't eat, or why she'd gone on a keto diet. I realized something was wrong around late November/early December but I didn't think it was about eating, she just seemed really sad and less talkative than usual.

By January she was in the hospital, not a psych ward just a regular one and she told me she'd been having "stomach issues" which I didn't question, if anything it made sense why she wasn't eating or had constant diets. She stopped going to school and I asked if I could visit her, she said sure. The day I was meant to visit she sent me a selfie and I saw she has a feeding tube. My heart genuinely stopped at that moment and by now I kinda realized so I just asked her directly, she said we can talk when I'm there. We talked for about 4 hours and she told me everything, but said that she wants to heal and wants to get better and by that point I had no reason to believe otherwise and said I'm here if she needed anything. I cried the whole way home but still had hoped she'd get better soon.

I visited her a few times from January to March but at the end of March I got submitted to a psych ward for personal reasons, so next time I saw her was about June.

We had lots of fun and I was worried about her but still had no reason to believe she isn't getting better or at least not going backwards. During those times she told me a lot about anorexia and how she struggled, and unknowingly gave me tips on how to hide the fact you haven't eaten, even in hospitals or how to lose weight quickly. I know she didn't mean it but she said it and it had a really bad impact on me.

After I got out of the hospital, she was submitted to one and by that point I realized she wasn't getting better. She told me many times she wasn't counting steps or calories but it wasn't true. It was all a lie.

We met in September at the start of school and I seriously hoped the hospital would help at least a bit but it didn't. We only had each other at school and I was still struggling with my own issues and so was she but I saw she's getting worse. She would spend all the recess walking around the whole school and even people she didn't know realized and tried to help, same with teachers. I tried helping too and she would always get mad at me but I just sat her down every time. She would say she'd do it at home and just to fuck off. I felt peace when she was in a ward again even if I know it might be mean, but I genuinely couldn't stand seeing that. I remember sitting on the floor crying because I couldn't stop her.

I don't know if she's getting better but this is how I realized this had a huge effect on me. When she came back I genuinely always walked with her even to the bathroom because I didn't know where she'd go. We talked about it and I told her the truth which she was aware of. There's a lot more I can say but I genuinely don't know what to do. I can't forgive her. I can't believe anything she says. I know it's not her fault but it isn't mine either. I'm not gonna tell her I'm angry with her because it's mean, I know she didn't mean it and I know she didn't choose to be ill but I'm just so angry I don't know if I'll ever forgive her or believe her again. I love her to death and I'll never leave my friends but I don't know if I can stay if she doesn't get better, since then I've relapsed with my eating disorder (she doesn't know) and I dont wanna get even worse but I also don't wanna end our friendship due to this, I wanna support her through but I can't even support myself. if she sees this, I love you N and I wish you the best.