You know maybe the point is she may not actually enjoy sex for some physical reason and is avoiding it. Meaning she may be having "moisture issues", she might not be getting aroused in the same way/rate as you, or even staying as aroused as you? I don't know what else to say to be honest. Confront....no confront is to harsh maybe, ask her to go see her medical doctor and discuss any kind of physical issues she might have concerning her body. Get KY and see what she says. If she still turns you down then maybe you need to find your happiness by moving on. As bad as it may sound that may be your only choice left....though I hate to say that.