I lost a brother already. I can't imagine what it would be like to outlive a child. The protagonist of New Amsterdam has outlived dozens of children and grandchildren. His dog is named 36! That's a lot of grief. The writers (and the actor) have done a good job making the character realistically optimistic. He'd have to be, to keep going day after day, year after year, century after century.
If freedom's just another word for nothing left to lose, then immortality is just another name for loneliness.
I hope they don't cancel this show! It might be speculative fiction, but it's a hell of a lot better than so-called reality-TV.