I think I am in the same position as you are, and there's always advice to people who got dumped instead of the people who do the rejecting. I'm a girl though, but the situation should be the same.

Rejecters also feel guilt and remorse, and it's not their fault they don't feel the same way for the other person who likes them. Personally I would give her space to move on a little, because you can't lead her on. I didn't want to hurt the guy's feelings so i decided to try it out, and it was my very first relationship, and both of us just got hurt, when I rejected him for the second time, so they'll think you lied to them, when in fact, you didn't, and then you end up losing someone you really care about. Don't end up the same way. We're friends now though.

Don't suddenly ignore her, and maybe you could just say both of you guys need a little time and space to sort this complication out a bit. And then when she decides to contact you because she missed you, (or smth else) perhaps the door to friendship might open again, a genuine one.

Try to be friends first and see where it leads. I hope this helps, and I apologise for the lengthy post.