I am a graduate student in my mid-twenties who is at a loss of what to do regarding my best friend of 5 years with BPD. She is hilarious, gorgeous, smart, and fun but struggles constantly with relationships, employment, and most recently the law. She is intelligent and knows what the consequences of her behavior will be, but can't stop making the "wrong" choices, i.e. the ones that inevitably cause her more pain and suffering. She has a degree but is going back to school. She is living off her parents money, and has been without a job for year though she could easily obtain a part time job. Though that is perhaps none of my business it bothers me because I value hard work and would never take money from my parents unless I had no other option--to me it seems she is taking advantage of them.
Our friendship has had its ups and downs as you can probably imagine. She seems to warp situations in her mind when she is going through particularly difficult life circumstances so that everyone turns into "the enemy". During these times it's exhausting to be her friend--I want to be there for her to listen, but eventually it starts affecting my life negatively because she can be so demanding and combative, even though I'm on her side. She has really high expectations for how she should be treated by her friends, but has been rude and extremely inconsiderate to me in the past. Any time I've tried to explain to her calmly and respectfully that sometimes the way she treats me makes me feel bad she becomes extremely defensive and turns the situation around, becoming angry that I'm expressing these feelings.
As I mentioned before, she recently encountered some trouble with the law as a result of being a relationship she knew was horrible. We had a little trip planned before this came about. When I asked her if she still wanted to go, she became really mad, eventually sending me a barrage of text messages with things like "I'm going to be sad either way, I thought the trip would be good to get my mind off things, but if you're just going to be frustrated with how I'm acting we're not going to have any fun so I won't go". I was just asking to be considerate of what she was going through, I didn't want her to feel like she had to go if she had other things she needed to take care of. That is just a minor, most recent example of an interaction with her, but it demonstrates how confusing it can be to be her friend. When that happened I just felt so exhausted--I spend so much of my time listening to her about her problems and trying to be a good friend and I don't feel like it's appreciated or reciprocated.
My other friends tell me I need to distance myself, that I've tried all I can, and that there's nothing I can do to help her be happy. Right now I'm feeling like that's my best option as well. I feel guilty because I don't want to abandon her but I don't feel like my friends should cause me as much stress and heartache as she does. It may be time to be selfish in the interest of self preservation. Any perspectives?