I'm going to go back to asking if you're sure it's not drugs making things worse. At her age, it is always a possibility. My daughter managed to use drugs even when she was homeschooled and (I thought) rarely out of the house. Sure, it could be a lot of things and maybe it is, but for a teenager it is never a good idea to dismiss drug or alcohol use. We had no idea our daughter was using drugs. She was diagnosed with bipolar (she doesn't have it) and put on medications and taken to a psychologist until she was finally busted for using pot (turned out she had been using a lot more). It is a common thing for an unstable teen to do and it only makes things worse. Some kids abuse over the counter medications or their own medications, especially if they take stimulants. Anything, it seems, for them to feel better! My daughter slept at odd hours, especially during the day, and fell asleep at school. She told us she had insomnia and didn't sleep well at night and we believed it. She was quite violent (often out of the blue) when she used drugs and we found knives under her mattress. She put her hand through a window once and pulled a knife on herself. It wasn't pretty.
Not saying that this is "IT" for YOUR child, but it could be happening...it happened right under our noses and we didn't take it seriously until she was much worse.
Good luck finding out the problem and keep us all posted. We do care.