Honestly, what she should be doing is pretty simple:
- take her meds consistently (set timers)
- go to her therapy and be honest throughout
- take better care of her grooming (trim her nails, properly brush her teeth and floss, bathe on a normal basis, etc)
- study for the GED and take it until she passes (it's actually much easier than you think. I know somebody as mentally ill as she is who has passed it. He said it was easy as fuck after some minor studying, and he dropped out in 6th grade!)
- do some part-time work while she figures out what she wants to do in life
There, that's it. If she did those steps, she would be in a much better spot. I don't think this is too much of an ask. But I gave her advice in my very first post in this thread, that she both acknowledged positively, and promptly ignored a few days later. So I know even this basic stuff will not happen. She'll probably stay how she is for years.