My primary partner for the past few years has developed a relationship with someone whom he has a deep emotional connection and a desire to have children with. Cool, we've talked about this and I knew it would happen sometime. In the past we've talked about me being involved hypothetically to whatever extent other partners are interested in co-parenting (I'm unable to have more kids of my own) and he tends to introduce me to the partners who he feels might be interested in exploring that path. She seems down with this and has been glad to get to know me, however, as I get to know her the less I like her. She seems like a mess of a person. She's currently in a traditional marriage and considers herself monogamous to both her husband and my partner (what?) and that she would prefer that my partner date only her (what??) but has told me that I'm 'okay' to stay with my partner (what???). I also found out that she drugged her kids with benadryl to get uninterrupted sexy time with him during their last visit and she's done other questionable parenting things. This is not a person I want around me, let alone as a coparent. Unfortunately while getting to know me she's developed a strong friendship with me and I'm not sure how to disentangle myself from that, particularly in a way that doesn't upset her or my relationships with my partner unless it's by his own doing. How badly have I screwed myself over, Reddit? Any way I can gracefully extricate myself here?