Let me explain why you've found yourself in that situation. First, to make you understand better, I'll take a typical scenario which I believe most of us are conversant with; Boy-Girl relationships.
Imagine your a lonely guy who insists that women won't come near you despite the fact that he is the nicest guy in the world. I can explain what is wrong with this mindset. "Nice guy? Who gives a shit?
"What, so am I saying that you can't get girls unless you have a nice job and make lots of money?"
No, your brain jumps to that conclusion so you have an excuse to write off everyone who rejects you by thinking that they're just being shallow, materialistic and selfish.
I'm asking, what do you offer? Are you smart? Funny? Interesting? Rich? Talented? Ambitious? Creative?
Don't say that you're a nice guy -- that's the barest minimum. Pretty girls have guys being nice to them 36 times a day. Saying that you're a nice guy is like a restaurant whose only selling point is that the food doesn't make you sick.