You're very pretty, so that instantly puts men on their guard. The nice, sweet guys think, "She's high-maintenance, or she's got an NFL linebacker for a boyfriend." This leaves the jerks who have little to lose.
You may also get men who wish to rack up experiences with beautiful women out a sense of hurt or bitterness. Those are the worst!
I've been there. All that's left to do is keep trying. I know - it sucks. But, that's that.