Anonymous wrote:What does she say when you ask her not to talk about them?
This is key. If she ignores your request that tells you a lot. Then you need to just change subject or get off the phone.
Sure nobody has to do anything, but there are consequences to that. My mother wonders why her friendships has faded and her family relationships are distant. It's because she has this attitude that she can do whatever she wants. If a friend is separated she will prattle on about running into their spouse and how great he's doing. If a friend has distanced from another she will make sure to guilt trip and will be the first to say "You know....Larla has cancer now, you should really reach out to her and get over whatever made you upset." Often these people play dumb and can dish it, but cannot take it. if my mom hears anyone say anything nice about someone she thinks wronged her, my mother loses it-even if she just overhears a conversation.
Basic courtesy is not complicated. It's not like OP wants to gossip and trash talk. She simply wants to have a distant and polite relationship and not hear about them between visits. On the spectrum of requests that is so minor.