She doesn't seem to know that what she is doing is hurting you. I know she has a mental illness and this may cause a lot of her emotional drama to you, but I think you should really just respect her wishes (not saying you aren't, you seem to be trying really hard to make things right) and leave her alone. She doesn't seem to appreciate or know what you are going through (again, it might be because of her illness, idk), but you should really take care of yourself. And that means no contact. There is no other way. Because as cliche as this sounds, if it's meant to be, it will be.

Take care of yourself and stop beating yourself up over up. You tried really hard to make this relationship work. It's okay to still have feelings, but you really gotta let go and take care of yourself first before you try to patch things up for anyone, including her.