to be less kindly than those above me, stop being so goddamned self-important. I can understand your feelings, but at this point it's just plain stupid to keep pursuing it. No matter what it was about, if a friend wants to keep something secret, it's not your business to pursue the matter. Plainly there's some reason that she's behaving in this manner, as others have said. If someone who's not your friend wants to keep a harmless secret, it's even LESS your business. Like Tim said, it's only going to land you hot water.

Find something else to worry your teeth on, and move on.