I think he prefers masturbation. Porn has ruined many men this way. I can tell you now that when you watch too much porn it does desensitise you and it probably is a combination of having too tight a grip while masturbating and being used to masturbation rather then actual sex.

You're probably right breaking up with him because he won't try anything, so clearly doesn't value you that much. There's even ways of masturbation without such a tight grip.