I doubt he is cheating. I think he has fears and may be with drawling. You both need to talk openly about expectations and clarify the way you feel and listen to him.
I doubt you are pushing him into it rather he fears what you expect from the ordeal. He also may fear he will hurt you despite wanting to be with you--he knows what you want & knows he cannot be that right now.
Talk...best form of a good relationship & be friends. Let the rest follow love, sex and when appropriate marriage & kids follow with the most correct person for you
