I've always considered this to be a circular problem. . .
Every man wants to find himself a princess (I don't mean a high maintenance whiny princess, but HIS princess, the classical fairy tale sense). Every woman wants to BE a princess and to have someone who will chase after her seek her, fight for, and love her.
Now here's the issue, too many women have already designed their "perfect guy" in their head and tend to jump from guy to guy trying to find the him, and believe me they won't find him, nobody will be as good as what you can dream up. (Many) women also tend to over sexualize themselves in an attempt to be "beautiful." I spent almost 3 years working in a night club and I can't tell you how many girls I saw dressed to the nines just trying to get attention, in basic biological terms, trying to find a mate. Sad thing is many of these girls would have been truly ATTRACTIVE (not just hot) if they weren't so whored up. Don't get me wrong, I'm still going to do a double take when some 110 lb 19 year old (drinking age is 18 up here) super flexible cheer leader walks in with a mini mini-skirt and a halter top, because it appeals to my biological urges. That being said her overall attractiveness to me goes down the toilet because I look at her and say to myself "what an attention seeking whore. . ." Then after this sort of girl has ****ed 10, 20, 30+ guys trying to make one of them "love" her she complains there are no good men left! Well guess what sweetheart if your going to dress/act like a whore, I'm going to TREAT you like a whore. . . Why would I be your knight in shining armor if your not going to be my princess worth fighting for?
Now to even it out, guys are just as bad, we'll do whatever we can just go get laid. I'm sorry to say I've seen more then one of my friends and co-workers lie through their teeth just to get some hottie into bed. What's the old addage? Women give sex to be loved, men give love to have sex. . .
Both genders also seem to have issues letting go of previous baggage, women who have been hurt be previous men who, to quote LizKat, used them up and tossed them aside like old cigarette lighters and men who have been scorned or cheated on by women who were themselves previously hurt by above mentioned men. See how it becomes cyclical?
Basically there ARE "decent" girls (and guys) out there but you really need to look long and hard to find them. Really your chances of having a chance with someone "decent" are going to be vastly improved by improving yourself, being a well rounded confident person.