Give her a dose of her own medicine! Next time she makes you get on top and do the work, fark her like you've never done it before and see how much she enjoys it. Let her know that sex is not something she has and can give to you, but rather something you both create and share together
if she doesn't get that and its a big problem to you (for most guys it is), then move on. When you find a girl who knows how to share the sexual experience... HOLY sh1t! You wont even be able to compare the two!!