Hi,
Your situation is kind of like mine, except we're not sure about our relationship status yet, but this is my take on it.
You've stated that:
1. She likes you more than you like her
2. you tried a couple times to do things to push her away so that she would detach herself from you naturally, but that didn't really work
so the way I see it is, you just have to break it down to her. I know it's soooo much easier said than done, but it has to be said. If you've been friends with this girl for 2 years, then you should be able to talk to her about ANYTHING.
By holding off and not talking about how you feel is unfair to the both of you because overtime you'll see that as your relationship continues, her feelings will only continue to grow and yours could possibly change, and you might not even want to be around her at all, if you hold off too long.
Hope that helps.