Loneliness Support Group
Loneliness is an emotional state in which a person experiences a powerful feeling of emptiness and isolation. Loneliness is more than the feeling of wanting company or wanting to do something with another person. Loneliness is a feeling of being cut off, disconnected and alienated from other people. The lonely person may find it difficult or even impossible to have any...

This is going to sound cruel, but if she has decided, after the help you have offered her, that this is how she is going to live her life then there really isn't much you can do. Especially if she is treating you poorly while you are attempting to help her. As kind as you are, you also need to look after yourself and if maintaining this friendship is causing you this much stress then it isn't worth it.
You can also take a break from her for a little while, if that is a bit better.
Good luck!
It's really painful to watch people who we care about suffer and it's even more painful and difficult to let go when there isn't much else we can do. I'm familiar with the feeling of wanting someone you care about who is in pain to reach out to you for help, but when that isn't happening it can be a tough pill to swallow.
Everyone's genetic makeup, life experiences, beliefs, and morals are different. It's taken me 29 years to realize that not everyone has the same kind of caring heart that I do, so I have to be careful not to let myself get emotionally attached to people who don't understand and treat me with the same respect and kindness that I treat them, no matter how badly I may want it.
Don't stop caring about others, just look after your own well being, mental health, and state of mind more closely!
Goodluck!
You have to look out for yourself now. Now yes its true that maybe someday she will come to her senses and want to be your friend again, and weather you accept her back into your life or not is your decision. But for right now, you need to stop letting her take you down like this.