My MIL recently mentioned me having kids again. She knows we are childfree and wont be having kids (I'm 40 and hoped she would get it by now, husband and I have been together close to 14 years). She said she wants grand kids and doesn't think her other 2 kids will ha e any either. When I mentioned that she has 2 grandkids (via her stepdaughter) she said "those aren't mine". Related by blood are all a lot of people care about and quite frankly it is disgusting. I reiterated that I will not be having children. I was appalled that she would say her grandchildren aren't hers because they arent related by blood.

OP is NTA and her fiance proved that he doesn't even care that his mother feels that way.