You sound like a very self-aware person who is trying the very best that he can in a world that is not always kind to those with mental illness. Your sister, on the other hand, appears to live in a pretty narrow, small world where only one set of opinions is permitted, her own. Protect yourself and those who value you and understand you. You don't have to sink to your sister's own level to set some boundaries with her. Based on what you've written above, she is the one out of line. You DO NOT have to feel guilty if you need to remove yourself, your step son, and your wife from her sphere of influence. She may be related to you, but she's not acting like "family." Family, at least to me, has nothing to do with blood...it's the way you are valued and respected. The rest is just biology.