Don't worry, it's no ones fault. As long as she's not lying there like limp lettuce then it's all good. Don't put pressure on her to orgasm, because the expectation will make it less likely. Just enjoy what you have, I am sure she does, if she doesn't feel the need to fake to please you. Go with it, you are probably doing everything right - if you don't think you are, then just pay her more attention in bed, sorted!