As far as the girl goes, be an ass to her. Honest to fucking god, it works.
There is this girl who I kind of liked, and she kind of liked me but there wasn't anything there. I moved on to someone new and she constantly nagged me about how I used to like her or whatever. I was just a constant ass to her, and still am. She can't get enough of me.
Just be mean, but not TOO mean. Talk to her like you would talk to your guy friends when you're messing around.
Don't be like "oh you're an ugly fat bitch and I hate you" but just constantly remind her that she's retarded.
Come to thing of it, I don't really recommend this at all. Maybe as a last resort, because I guess if you do it wrong it could be bad. Works for me, though.