Guys complain about this a lot, and they have every right to do so. Girls really do fall for douche bags instead of nice, respectable guys. The question is why? It's not like we want to date selfish, cocky, idiots, but somehow countless girls do.
Yes, I just included myself in this discussion. I find myself continually attracted to muscular guys that are more obsessed with their bodies than I am. And I'm a girl. They are totally self-centered jerks, and yet I'd totally make-out with any of them. Yep, I just said that. This never made sense to me, I absolutely HATE these guys, but there is something beguiling about them.
So here's a theory that explains why girls fall into the douche bag trap: These jerks develop a false sense of superiority which makes them confident. I find confidence very attractive. Girls might say that we want a sensitive guy, but what we really want is a manly MAN. The problem arises when girls mistake the jerks as "manly" when they're really just egotistic losers.
I may be attracted to countless retards, but I would never date one. I respect myself enough to avoid that situation. But it really bothers me that I'm physically attracted to jerks, and yet I can't feel this way towards "nice" guys. Do you know how many guys I've wanted to like, but just couldn't? A lot. I hate how there's this perfect, friendly, cute guy, and yet I don't feel anything. IT DOESN'T MAKE SENSE. Maybe they're so respectful, I feel like they'll never make a move. I don't know. It's weird.
So this is my advice to you nice guys: If you've been friend-zoned, don't change who you are. Girls are stupid sometimes. Ok, a lot of times. But if you want them to notice you in a "friendlier" manner, you're gonna have to show some confidence. If you want to kiss a girl, and she seems to have mutual feelings, then GO FOR IT. Girls like to feel like the guy is in control. WARNING: No other time will we be ok with guys being controlling or dominating; that's when you start blurring the line between manly and douchey. Having said that, we still want you to be confident in yourself as a man. I don't care if it's old fashion, the guy should be the one to make the first move. If I think he's too chicken, then I'm no longer attracted to him.
The important thing is to continue and be a nice guy. Sure, right now you may feel like girls don't notice you in the way you want, but you don't want to date those girls with low self-confidence anyway. If the only reason you have a sub-par dating life is because you're nice, then you don't have much to worry about. I've been friend-zoned a few times too and it sucks. The problem is, I can't use the excuse that I'm too nice. It doesn't work like that for girls. No, the reasons I came up with include: I'm obnoxious, I'm annoying, I'm weird, I'm flat, I'm not very ladylike, or a nice combination of all those things.
See? Just compare your life to mine and you'll feel better about yourself!