you sound like you need a lad's night, actually several. if you know you feel worse in the evenings then meet up with mates or whatever until these feelings start to go and trust me they will. you know she's not at home crying over all of this so head up and don't let it affect your studies and friendships. 'bro's before ho's' and all that.
remember she has flaws like everyone else she's not as perfect as you make out. this makes me think that you don't know her THAT well.
They called us a dead generation,
They told us that we wouldn't survive
They left us alone in the maelstrom
As you can see we're all clearly alive.