Have you ever rejected a woman's sexual advances? If so, how did she react and what was the outcome afterwards?

The general assumption women seem to have is that men are always horny and eager to have sex.

So I'm assuming if you reject a woman's sexual advances on you, say you're not in the mood of whatever, it must completely fuck with them.

EDIT: If you rejected her when you two were in a relationship, specify that, since that's important.