I'm curious... I've been with my BF for a year and a half, and for the past couple of months he hasn't wanted to have sex. I've asked him and all he does is apologize and says he's just not feeling sexual. He says he'll try and nothing changes...Its starting to take a toll on the relationship. He doesn't give me any reason other than I don't know...What are possible reasons for a guy to lose his sex drive completely like this?