Ugh! I’m so very sorry you are going through this.
Our lives were very chaotic due to our son. We enrolled him in a boarding school for juvenile teens. Yes, it is expensive but the past 12mo have been so peaceful! His school definitely has an institutionalized feel and I wish he would receive more therapeutic care, however he’s not a willing participant. But it does offer us solace knowing he is safe, not on the streets, having a warm place to sleep and regular food to eat.
Have you discussed emancipation with her? You would have to go through a lawyer/court but you would no longer be held responsible for her.
Can you get a bank loan to assist paying for a boarding school?
I hope you are able to get some plans in place and find some relief. Hugs to you!