NTA that's some psychological manipulation she's inflicting on your family; she can do as she pleases in her home but not in yours & certainly not without both your's & your husband's consent. She is the grandmother, not the mother & she should not be interjecting herself into how you care for your children; you were right to keep your distance for at least 6 months since you'd be in a vulnerable state. Hearing her speak about her antics so blatantly as she crossed a much needed boundary would be justification for me to cut her off entirely; I wouldn't want her emotionally scarring or psychologically manipulating my impressionable children with her outlandish beliefs.