Cognitive exertion interacting with talkative people

Several people I love dearly, including one I live with, are big talkers —- as in lots of long stories with many tangents. As much as I want to spend time with them and to engage with what they are sharing, the cognitive exertion is often too much. Brain fog, dizziness, derealization will hit mid-story and I struggle to remain upright let alone hear out the full story or respond to what they’re sharing. I have yet to find an easy way to kindly signal what’s happening, prod them to wrap it up, or excuse myself.

Have any of you found ways of dealing with this that at least sort of meet both parties needs for rest and connection? Do you have to completely isolate yourself to get quiet down time?