I think you really need to address this issue with him. My fiance has never done anything that but it sort of sound like training an animal or a really small child- when they do something you don't like you punish them, often physically, and sometimes what they did wrong as a sort of negative reinforcement technique. (little kid touches stove, it burns him, kid learns that that action gives a negative response, kid no longer touches stove... you cut, it is used as a punishment by someone else i.e. negative response to you cutting, you no longer cut <- I know not realistic result but my guess is somethign along that line is going through his head... keep in mind this is just my guess as to what he is thinking).

I wish you the best of luck at dealing with this situation, I really feel you need to confront him about this (in a non-aggressive way) though.