At wits end

Hi, I'm struggling to support my 21 year old daughter who has BPD, CPTSD, and OCD. She lives independantly about 1.5 hours away from me in a self contained studio flat attached to a house. She is miserable and has been clinically depressed for almost 4 years. I have exhausted myself trying to help her. She refuses all help (except for financial and practical support) and distrusts the medical sector thinking it's all set up to fund Israel. She won't take meds, she won't go to ER, she flatly refuses to see a counsellor or pyschologist (she's seen a few in the past but once they tell her something she doesn't like, she refuses to go back). I have 5 other kids and a demanding job. I've turned myself out advocating for her, taking her to appointments, helping her with her life admin, as well as providing signficant financial, emotional and practical support. She has systematically pushed away the rest of her family and friends and disregards anything good they bring to the relationship, and focuses instead on their flaws. She hates where she lives (although it's a sought after suburb), hates her job, and hates her life. She says 'only the children in Gaza' have it worse than her and she genuinely believes it.  Every day she has suicidal ideation and says she doesn't want to wake up, which is heartbreaking. She responds to her family's attempts to support her with contempt and anger. She doesn't want to be near any of her younger siblings (some of whom have special needs) and will snap at them and be nasty. She agreed to come to the GP yesterday, and for once, i had a ray of hope that she might accept help. The GP was kind and empathetic, and offered the usual supports, asking the standard triage questions and encouraged her to come back in 2 days for a mental health plan, ordered blood tests and wrote a script for an antidepressant. She stormed out and said 'take me home, i'm not doing any of that!'. I am at my wits end and i no longer know what to do. It's beginning to affect the broader family and my own mental well being. I'd be grateful for any guidance or advice from people who have gone through similar things. I'm terrified my daughter will do something to harm herself yet i'm hanging onto my own sanity with a mere thread.