My friend (Fake name will be Amelia) has multiple diagnosed mental illnesses. Looking back at it, my reasons for not wanting to be her friend, coincide with her mental illnesses

I met Amelia 3 years ago and I thought that we were somewhat good friends. She acted like a good friend and put effort into our friendship. Now, because of her illnesses it feels as if our relationship has been thoroughly tarnished.

Before I am witchhunted, I want to explain myself

Amelia isn't the best person. She lied to get me away from some of my friends, victimizes herself constantly, and is just constantly negative towards me. 

I did add the Mentally Ill part not for clickbait because I believe it directly links to our failing friendship.

I feel as if she uses her mental illness as a personality trait. It is all she will talk about now. I am not her therapist. I am her friend. (I am not leaving her because I hate her, it's just I feel like our relationship is becoming toxic) I am down to listen to her issues, but her constantly just throwing it into my face is just, making me feel awful as well.

I have 5 out of my 8 classes with her so I see her for the majority of my school day so she is a constant influence on my day. 

I really started seeing issues with her when one of my friends sat with her on the bus and didn't talk to her and Amelia blew it out of proportion and started saying all these awful things about my friend and attempted to really harm my relationship with my friend of 6 YEARS!!!!

I brushed it off and continued with our friendship. We really aren't fighting or anything right now but, she got a bad fever and stayed home for a week so I was Amelia-less 

If I am being honest, it felt great. I felt more open with people, I felt more positive, and it felt great. I feel awful that I think this way.

I haven't really explained the mental illness part of me not wanting to be with her. I briefly mentioned it but, she just exploits her illnesses. She constantly brags about her panic attacks and undermines my issues. I just feel like my problems aren't important when I am around her. She doesn't really understand my issues???

I have intense anxiety and an issue with people touching me. I am an introvert who only gains confidence from being around friends. She would put labels on me and just put my feelings below her. I just feel awful when I am around her. 

I am sorry if this is all over the place, I just wanted to pour my feelings out and get some opinions. I feel like I can't leave our "friend group" because I was told by the other two people that I am the 1 person who keeps the group going. I feel as if the group is going to fall apart eventually. 

Amelia was a great person and I just think she needs a friend who will be able to accompany all her needs. AITA for just wanting to leave our friendship?