Why don't I attract guys?

I'm 19 and have only had 2 boyfriends before. I've gone on dates that end up going nowhere and I've liked my fair share of crushes who turned out to be players, jerks or both. I can NEVER seem to attract a guy who ISN'T one of those attractive player types. Attractive, sweet guys never approach me, the attractive, jerky BAD BOYS do. Why don't the good ones approach me? How do I change that? I SWEAR I have a good personality.