[The Saucepan Man]

Never thought I'd be giving an answer based on Christianity in this forum, but ...

Generally, people who believe that they will go to heaven when they die are no less reluctant to die than anyone else. Perhaps it was the same for the Elves of ME. They were reluctant to go to their paradise before their chosen time. And I would have thought that they would certainly have preferred to go under their own steam rather than via a painful death.

As for those who chose to return to the Undying Lands, I would speculate that they were Elves who had lived many years and were weary of ME. Assuming that's correct, they were, in a sense, choosing to die of old age. And it would not have been cowardly to do so, even before Sauron's defeat, if they had lived so long and perhaps earned their right to go Valinor already.