The girl is not going to be waiting for you at the end of the rainbow. You already said she was involved with someone else. That means she won't come running if she sees a note.

As far as leaving without notice, well that might not be the most intelligent thing you've done but I do know the feeling. You haven't mentioned that you were independantly wealthy so I'm assuming you will have to work sometime in the future. Your next employer may thing not be so open to your intelligence and winning personality if he finds you left your current position without notice.

I hope things work out for you. If hospitalization will work for you then go for it. For me I will never go to the hospital again. For me I'll take the other way out.