Refuse to be physically intimate with her. Seriously, it reminds me of a man complaining to his doctor that "it hurts when I do this"--the doctor's reply is "then don't do that." If playing that game of hers bothers you, don't play.
But love is a drug, and we are all addicts. You can't just simply stop because you know it will hurt you, and playing that way is playing dirty and will get you no where but hurt worse in the end and eaten up with your own guilt. And THAT hurts worse.
Let me suggest that LOVE takes many forms, and can change over time. The intimate love CAN change to a friendship just as important and as deep as a lovers love. It takes time and adjustment, but it CAN happen... IF you do not play dirty.