not sure what to do about a girl

so basically there is a girl who has a crush on me and I'm not sure how to reject her as nicely as possible.
Her friends told me that she likes me and I'm not sure if she's aware of this or not. It would be difficult for me to bring this up without possibly revealing that her friends told one of her secrets or without it being really awkward.
I can't just go out with her on a whim (I've tried stuff like that before and hated it).
I feel guilty because I feel like if I don't reject her then I'm leading her on..
I can't stop feeling guilty for the way I am.
I remember that I've been kind of unfriendly to another friend of mine and now she's ignoring me. But it was because she kept coming too close to me. I hate the feeling that I've hurt someone.

should I just tell her what her friends have been saying and confront her about the issue?
Should I just keep ignoring the issue?

Its not your fault you have SPD. You shouldn't feel guilty about it. If you feel you won't be happy or you aren't able to do it, then maybe you shouldn't. I think if you do confront her about the issue and you feel like you have to explain why things won't work out, she'll understand. I don't think you should ignore it, especially now since you know about it. But even if you explain to her, and she says she understand- she may be heart broken. Its not your fault if that happens. All you can do is treat her with respect and be kind.

hmm gawd. i hate confronting people. I rarely speak to people about anything personal. It's so easy for me to ignore her feelings, but it is wrong. I know that if I liked someone I'd want them to react in some way (which has ruined me many times before). I guess I should talk to her online (also very rare for me...)
Other opinions are still appreciated.

As long as she doesn't act on her feelings I don't see why you'd have to explain yourself... downplay any flirtation and she'll get the idea to move on. You don't have to confront her and you'll save her potential embarrasment and animosity towards her friends.

ahh nice. 2 conflicting suggestions. I think I'll probably do what need4weed suggested because its easier and not irrevocable.