Dude...don't be so beat up by it. Trust me, if she's not into you, there's no reason to go after that. But only give up after you've actually talked to her. Don't listen to her friends, they can, and usually do bullstuff you around. You have to talk to her, and when she says she's not into you, then you move on.
But don't feel broken by it, it's not the end of the world.