I think Mike is right, you might want to consider a smaller university. I went to a small university to do my undergrad. 2500 students, only about 120 of those were music students. It was a great experience, I had so many more oppotunities to attend and participate in Master classes, you get to know you're profs, and fellow students much better. You would be surrounded by people interested in the same things you are. I also know that it is quite expensive to attend NYU, are you working a job, on top of school? Because by the sounds of it, it seems impossible-you do need time to yourself, and that time should not be spent in a little white room with a piano.
If you are looking for a good well rounded education, you might want to consider looking at the schools in Canada. Since I'm from Canada, I can tell you that Saint Francis Xavier, Acadia, Dalhousie, and Mount Allison universities all have excellent music programs, and with the current exchange rate, it wouldn't cost you very much to attend. I'm sure there are schools like these in the US which you could research. But at the same time, I've just moved to the US to go to one of the biggest music schools and people here seem very involved, and interested. So, maybe NYU isn't offering you what you need, but you could find that at a big school if you know what you're looking for. Does that make sense?
I also wouldn't recommend practicing that much a day. It seems a bit much. I was always able to accomplish what I needed in 4 hours. The only time I ever practiced this much was the month before my grad. school audtions, and I too almost had a breakdown!
Take it easy, you don't want to injure yourself. And, if you aren't enjoying your degree, change it so that you do. You would probably regret all of those long hours if in the end you didn't enjoy every minute of it.