Should I Try to Force it?

I am with my amazing boyfriend of 6 months and life is pretty good. I jumped into the dating game late, so he is my first boyfriend. Not too long ago, I was talking to one of his friends about relationships. His friend seemed very interested in how our relationship was going, because my boyfriend claimed to never have masturbated before. My boyfriend told me about this in the past as well and I totally believe him. When we first started getting funky and I would try to give him a hand job, he would as politely as possible tell me that I shouldn't try and that it doesnt work. I think that I have turned him on by just grinding against him and he's given me some verbal cues, but I'm worried. Should I ask him to try again? Should I ask him what's up? I have the feeling that if he doesn't masturbate he really means that he can't cum. Any and all information you have for me is greatly appreciated! ADDITION: I asked him how I can help him out in bed, and he just relpied that he gets enough enjoyment from making me happy.