Primarily for trying to break up my marriage because they did not "approve" of the person.
First time it happened when I had dinner with them (my then-fiance was at the table as well), and my mother proceeded to speak to me in our language (my fiance did not speak this language) asking whether I can leave him.

Second and final time, when I thought that I could have overreacted, and I called my mother to speak to her. At that time, I was expecting a child, so my thought was to establish peace and then break the great news to her.
Instead, she proceeded with asking me when will I leave my husband.

It was a final straw. I never spoke with her since (a decade now) and not planning on doing so until she comes to her senses.