First off, It just might be depression, but at times everyone's (I'm guessing) lives start to feel like it just isn't heading anywhere.
School IS repetitive, so that shouldn't be much of a worry, now would it?
If this girl really does care for you, I think you should wait for her. Give her some time, but don't wait too long. You don't want to be single for long just because she needs her space.
About the whole your friends getting drunk deal, ease up. What I mean is, have fun alittle. I'm not saying you should join in their drinkingness (Couldn't came up with a word). If your the type of guy that can't stand drunkeness, find new friends.
I feel the same way. I remember my ex (girlfriend at the time) and a teacher talking about going to college, and I was just standing there like a idiot. I just felt like shit knowing all my friend knew what they were going to do with there lives, and I didn't.
Ohh, and the chad is right, this is in the wrong forum, I would say.