I think the less you say, the better. But you have to make the call on what your actions are going to be. The bottom line is this is driving you nuts, and you want to be a happy man living his life and spending time with girls who want to be yours. You can't do that when you're holding out on one.
It happens though, I myself got a "friends" thing recently. At that point I just walk away and let them take it from there. My gut tells me there's something there, but I know enough to walk away and let it happen on its own. Dude, if she wants you she's not going to let you get away. It's as easy as that. And if she doesn't, then you're BOTH better off. She doesn't get in a relationship with someone she doesn't want, and you don't waste time on someone who doesn't want you.
You're at a crossroads here. You're not friends. You don't see her as a friend, and it's sapping up your energy. You want one thing from this girl, a relationship. Fine, that's what you want. THAT'S what you want, not a friendship. You have to pick one.
And one thing you have to just stop doing is worrying what she'll think about you or what her interpretations of what you are doing is this. You want to be with her, and unless and until that happens, you leave her alone. If she comes after you, you have to decide on that "gut level" if she's just trying to hold on to a guy that makes her feel good about herself or if she sees the man she wants drifting away from her.
By walking away, you are sending a strong message to her and yourself: and that is you don't get caught up in these friendships with chicks that you want to be with. You're not strong enough to handle it. And that's fine. You'll be stronger when you're doing the right thing for YOU. Not for her, or for the SS community, for YOU.