Gmelon, I don't think this is about "two wrongs" or "an eye for an eye." It's about protecting yourself. Since this person is a family member, as another poster said, you might not be able to go fully nc (no contact). But you can go lc (low contact) or vlc, and I highly recommend it in this situation. In fact, I suggest making up your mind to only see this person on those family events that she's invited to, and not inviting her to any you host, if that's possible. Also, if you run into her at such events, you only need to say a polite, "Hello" and move on. You don't need to engage in conversation with her. If she comes over to you and starts complaining about your behavior, change the subject or walk away. If she calls, emails, etc. with her gripes, just ignore them. Please don't give much thought to what she has to say because she is just trying to guilt-trip you back into her web (so to speak) so she can go on doing more of her bad behavior. Let go.