Not rambling...that was very clear, imo.
Well, if moving to lower-LC is not an option for you right now, what's left?
I think it's that you can change the feeling and atmosphere and direction of your contacts with her.
You can't change her. But you can still set boundaries within conversation (conversations with Nmothers are a great arena for, literally, practicing boundary-setting--looking at each contact as another opportunity to practice assertion, and boundaries. It can be a very healthy way to make changes within the same quantity of contacts. You can choose to change the quality if you don't want to change the quantity).
Examples would be:
--changing the amount of time you spend on the phone
--using a timer for yourself to end things after a time period you have previously decided you'd like to spend on it. (Iow, not being led simply by the fact that you are talking with her...to an open-ended amount of time. You CAN tell yourself before you choose to answer a call from her: I would like to be on the phone for 10 minutes. Then literally set a timer and when it runs out, you take an action.
--intentionally changing your tone of voice
--doing other things to control the conversation rather than just react to it, such as
....ask her questions in a new subject area you don't talk about normally, like old family stories, get some useful/interesting history
....change the subject if she begins repeating about something you know you don't want to discuss (really DO that, this is boundary-setting
....set some new limits on yourself as to what YOU are willing to talk about
....set cues by the phone to remind you of a NEW behavior you are going to undertake during the timed call, such as a breathing exercise
...intentionally change your tone of voice again. Stay conscious. Beware feelings of hypnosis.
--change the location of where you talk to her. If you usually sit down, stand up. Go outside and plant something (great antidote, to have your fingers in a pot of dirt, connects you to something larger and more powerful than a phone conversation).
--use the speakerphone for the entire call and while it's happening, decide to chop 6 cups of vegetables. Freeze them.
--use the speakerphone and clean something very carefully
--use the speakerphone and go through a pile of clothes or linens and select 1/3 of them to donate
--use the speakerphone and paint a watercolor (if you did a watercolor during every Nmother phone call, you'd have a body of work)
love,
Hops