That's really known of your business.

You need to talk to your supervisor about this. This is exactly why she is being nice to you all of a sudden: she knows she's taken things to far and wants to prevent you going to your boss by being nice and complimenting you, but all the while she's planning on lashing out at you again. I know someone here who is like that and all this person is doing is sucking me into this person's drama and trying to make me look like the bad guy. There's no way to block her in real life, but avoid conversations with her.