okay, i just saw the response posted to the comment above mine.

i would give her the number for a hotline, just in case. several years ago i was in a very similar situation to yours (while also dealing with depression and my own poor mental health): my friend's family prevented her from getting the help she needed. she ended up calling a hotline, and she also went to a youth center. since i don't know where you are located or what is happening with your friend, i can only recommending starting with some hotlines for depression (and on from there).

i hope things get better <3