This guy, is probably confused himself.
Have you ever been in a love triangle where you find yourself liking two people, and telling them both how you like them?
I'm pretty sure its the same problem the guy you like is having.
And I don't think hes using you in this case. He hasn't done anything to you but said he liked you but he likes another girl.
Just in case though, don't fall hard for him. It's okay to like him, but if he's in a love sitch right now you should at least give him space to think about who he wants to date.
When the time comes where he cant decide (or shows it) and your through with waiting find somebody else because chances are there IS probably a good chance youll find someone better then him