Hypersexuality a deal breaker ?

SO is recently diagnosed BPD male and always been hypersexual. He needs group sex, swinging, etc., wants to see me with other people. I just want monogamy but if I say no, I feel pressured into doing more. He’s very subtle with the pressure to where it feels like my fault for giving in and then hating myself after. I feel disgusting.

Anyone deal with this before?? Any help welcomed.