Being a nice guy won't get you anywhere. This is coming from an ex nice guy.

You're caught in the mindset that if you're nice to people, they'll like you. The nicer you are, the more they'll like you. Are they being mean? Well shit, you're just not being nice enough then!

This is wrong. So very wrong. It's usually an excuse to avoid conflict, either the guilt of being mean, or the fear of someone possibly being mean to you in return.

If you're nice to everyone, they'll just walk all over you. Male, female, irrelivant.

If you don't learn how to be mean within context, and to stand up for yourself, you're just going to be weak for the rest of your life. You'll never get anything you really want.

If you're nice to everyone, and you have a girlfriend, then she's probably just as pathetic as you are. You'll end up satiating each others existance, and neither of you will grow.

Girls want to attach themselves to someone who can provide, someone who (they see) is strong, and can deal with things so they don't have to. They can argue this point ad infinitum, but human basic instinct/primal drive will always win out in the end. Guys will always initially favour the pretty girl.

Learn this, the modify it to fit your own behavour. The more you cry about hopelessness, the closer it gets.