I’ll start off with one, Being upset about a breakup that happened hundreds of years ago.
Edit 1:
- Heath death of the universe, Death of the sun, etc, does not count. I feel like focusing on this is an overused point.
Edit 2:
- Loneliness does not count. I feel like we all know immortality means you’ll miss people and lose them.
Based on your question, you might dig the book “Boat of a Million Years.” The author put quite a bit of thought into just that.
https://en.m.wikipedia.org/wiki/The_Boat_of_a_Million_Years