Yea just another +1 on the subtle signs thing...we suck at picking up on it.

My friends current girlfriend is kinda the same way, was funny she was talking to us one night about all the subtle signals she was giving him that she wanted to date him and they were things like "I would shove him playfully" or "Id laugh at his jokes" to a guy thats just regular behavior...i mean i punch my best friends in the arm just for the hell of it sometimes.

edit: I will also say, dont try and force anything. Not that i think you will but please please dont, it only brings sadness and problems. Let it come to you.