I agree with the hospitalization suggestion. I was a quiet, studious, nerdy teenager. Then I had my first episode at 18 and started to behave exactly like what you're describing. I have been going downhill ever since, and it wasn't until I was hospitalized that I realized it was time to get myself together. I had a bit of a relapse after I left because I didn't really have the strong support system I needed. It seems that your daughter won't have that problem. Good luck!