19 year old and no sex drive

I have absolutely no sex drive, it's been months since I've masterbated, my partner wants to have sex though and I don't want to at all. He tries so hard to try to get me turned on and j know he's frustrated but I have no interest. I'm emotionally and physically attracted to men, but I just am never in the mood for sex and I believe that it definitely helps improve the intimacy in the relationship and there is none. When I was 13-14 my sex drive was freakishly high, but after losing my virginity at 17 it has crashed down to where it is nonexistent, at first I thought it was because I was taking BC, but after being off of it for a week I feel no different. Has anyone else experienced this?