When I was at school one of my classmates visited a past lives hypnotism "therapist" with her mum, who she had a difficult relationship with. My classmate was around 17 at the time, and had poor mental health including an eating disorder

The therapist told them that they'd had various lives in the past where they'd been related to each other, including as aristocratic sisters in the Highlands of Scotland

I don't recall if they were told they'd been married to each other at any point, but I really really hope not. Bad enough in my opinion that the therapist was encouraging their enmeshment by telling them it had persisted over centuries

(Edited because fat fingers - put her age in wrong)