Oh, I'm bad with this. Not mean or anything - but I'm old enough now that I really do feel my time is limited and I'm not willing to give it away for stuff like this anymore.
Because in my experience (others' may differ) these folks never, ever have time to listen *back*. It's never reciprocal, and at my age that seems to matter a lot more than it once did.
(Or if they *do* listen back, you find whatever you shared with them coming back at you, distorted into something hostile if not unrecognizable, from some indignant third party. "X told me you said THIS AWFUL THING" when you never said anything at all like Awful Thing. Ugh... )
I'm not mean or even particularly direct - I just wait until they have to stop for breath and cheerily excuse myself. So much to do, been lovely to see you, etc.
Kudos to those who can field this better than I, you're gathering crowns in Heaven for sure.
_________________
"I believe you find life such a problem because you think there are the good people and the bad people," said the man. "You're wrong, of course. There are, always and only, the bad people, but some of them are on opposite sides."
-- Terry Pratchett, Guards! Guards!