Unfortunately, women will choose the real diamond every time. My wife has a PhD in chemical engineering, understands that the fake ones are actually technically superior to real diamonds, and knew that she could get a bigger, better diamond for the same price, but insisted on a real one. I even made her watch Blood Diamond a week before I proposed. There's just something about digging a rock up out of the dirt that instills it with some sentimental value for a woman... Either that, or de Beers marketing is really that good.
No offense but your wife sucks.