I think my friendship with my best friend is done, Their bpd has gotten so much worse, like BAD, to the point of idk if theyre able to keep up a friendship.. my mental health has gotten worse. I cant?

Maintaining friendships with someone struggling with mental illness and as a person with mental illness is difficult. It can be hard to balance seemingly conflicting factors such as wanting to be supportive & helpful towards someone you care about and who is having serious symptoms of mental health, while also wanting to keep healthy boundaries and maintain your own mental health. For me, it has been helpful to be realistic with my limits. Sometimes, the help that someone needs is beyond what we can give, and that's OK. I believe that setting boundaries, clear & honest communication, and maintaining a supportive tone can be tools in navigating these specific friendship challenges.