Thank you guys, it really helps me to hear all that! I was thinking very much along those lines as well. This is his first poly relationship and the first person we are adding to ours (well, not quite yet, but possibly). I am communicating to him my needs, which he feels defensive of. Its an odd situation, and I am just going to ride it out and see where it goes.
To update: He told her he loves her and she is in a LDR with a long term bf, so she said, "You know I can't say anything back". Damn, how terrible of her to not just make up her mind! I can just see her leading him on for the rest of the summer then going back (shes here for an internship) to her bf and crushing his heart. Sigh, we shall wait and see.
Have courage to continue this journey, for it holds nothing but lessons and wonders.