Nice guys only finish last because girls are stupid and don't realize what they have until it's not there anymore. For what it's worth, I think you're a cutie!
There's a difference between being nice and being a doormat. Saying "girls only go for assholes" is misinformed. Girls like confidence, they don't like to be put on pedestals, and the ones who go out with the BMW-driving date rapists aren't worth your time anyway.