Alright here's my dilemma: Just graduated high school, in freshman year there was a girl I fell in love with. So I did the usual be friendly, get to know her and whatnot. About halfway through sophomore year I asked her to be my gf, she rejected me. So then I decided whatever and over the summer of my junior year I decided to be a little less extreme and asked her out on a date, again rejected me, like she has every single time I've asked to just hang out. every. single. fucking. time. then she tells me that she doesn't want to date anybody while in high school. well I was hanging out with some friends a few weeks before grad and found out she dated a guy around the end of fall/begin of winter. now that just hurt and pissed me off because now I think she lied to me. So, how do I find out if she lied to me? I know I should try asking her but she could always lie and tell me no.

tl;dr: girl I'm in love with, want to know if she lied to me. also how to quit thinking about her because it's driving me up the freaking wall man!