A Psuedo-Scathing Rant

I need someone to explain something to me.
I need someone to tell me why, exactly, nice guys finish last?
Yeah, I know that a level of niceness doesn't exactly breed competition. I know that.
But I still don't get it.
In this world there are guys who are nice. Guy that can be trusted with your life.
Guys that can keep secrets if that's what is asked of them.
Guys that won't hurt you.
Yet, for some reason, these guys always seem to be alone. It's like no one will give them a chance, even though it's a known fact that these guys are not going to hurt you.
I see guys who are jerks to everyone, just complete and total wastes of time... but these guys can get any girl they want, and then when they hurt said girl, said girl goes to the nice guy and complains, and will sometimes go so far as to say "I wish I could find someone like you."
Well, HELLO!!!
We've been here the whole time. Getting screwed every time we turn around because we're not the jack-hole that, yeah he might look like Brad Pitt or whoever, he's still gonna tick you off and hurt you. And you know that we won't. Yet, we still don't get the chance. And I'll admit something: it's beginning to piss us off.
Everyday, we hear what nice, sweet, loving, caring guys we are. Everyday, seemingly, we hear about how the other guy has wronged you. We hear about how you wish you could find someone like us. What are we? Imaginary friends?
I know I'm sounding quite whiny at the moment, but this crap has to be said. Because the nice guys are getting ticked. We're slowly becoming the jerks that are hurting you now. We don't want to be, but we're running out of options. Guys may act all big and tough, but there's only so much crap we can take before we stop altogether.
Remember that. Remember that when your jerk boyfriend cheats on you. Remember that the next time you tell a guy that you wish you could find someone like him. Remember that he's hurt too.
I'm saying this because it's true. The nice guys are becoming fewer in number, because they see the jerks getting whatever they want, and so the nice guys turn to being jerks themselves. Those of us who have tried to remain nice, well, we're becoming jerks inadvertently. We don't want to be, but we're also tired of being hurt.
We're tired. We wouldn't hurt anyone, and yet we live in constant pain and misery, wallowing in loneliness because we know no other way to be.
I honestly think that the nice guys in this world are better than the jerks, I really do. But the nice guys are doomed to finish last.
So can someone tell me why?