Immortality - Blessing or Curse?

An allegory of immortality
Giulio Romano

In Hindu mythology, the following are generally considered the Immortals:

Veda Vyasa, Parashurama, Mahabali, Vibhishana, Anjaneya, Kripacharya & Ashwatthama. For the last named, it was a curse, as he had to lead a painful life.

For a modern look on the subject, one need go no further than Natalie Babbitt's "Tuck Everlasting." As summarised in the Oxford Companion to Children's Literature, the Tuck family have drunk from water, that has made them immortal. When they think that  Winnie Foster, a young girl, has guessed their secret, they kidnap her & try to persuade her of the realities of living forever.

This novel, less than 140 pages, examines the practical difficulties of being immortal in a mortal world, the plot enlivened by a kidnapping, a killing, a jailbreak & the ultimate renunciation of immortality by Winnie Foster.