My mother has been obsessively talking and obsessing over her partners child for 4 years. My siblings actually warn people. She can't stop talking about her and involving herself this person's life. She will incorporate her name into every conversation even with complete strangers. Everything relates back to this other person. People can't cope being around my mother for too long now. She even acts jealous when she talks to her own mother or makes a decision withbout her involvement. It's very unhealthy and strange to witness. My mother's caused so many problems by over stepping boundaries in her partners family that no one wants to associate with him while he's with her. Its not all good stuff she talks about. The relationship between them started off nice but the daughter has tried cutting her off and for the last few years even with no contact she stalks her on social media and bad mouths her. She still doesnt talk about anything else. What is going on?