[Guinevere]

Originally posted by Child of the 7th age
To be truthful, at the end of the book, I find myself grieving for a world, for a past that never even existed. Rationally, I understand that. Yet, part of me does not want to accept those limitations and still yearns for something that feels as if it should have been.

Beautifully said! I feel very much the same as you wrote!
The ending is bitter-sweet, sad and yet hopeful. When I finish reading the LotR, I feel sad, but not depressed and empty!
I think this ending is beautiful and perfect, even if it makes the tears rise in my eyes. It is just like Gandalf says:

I will not say: Do not cry, for not all tears are an evil.

I feel that there is a balance between hope and melancholy, that there is a merciful providence behind it all, in spite of the sadness that many things are irrevocably lost.
I think the following quote expresses this mood very well:

Then Elrond and Galadriel rode on; for the Third Age was over, and the Days of the Rings were passed, and an end was come of the story and song of those times. With them went many Elves of the High Kindred who would no longer stay in Middle-earth; and among them, filled with a sadness that was yet blessed and without bitterness, rode Sam, and Frodo, and Bilbo, and the Elves delighted to honour them.

The ending of the tale of Aragorn and Arwen is even more sad, although Aragorn’s last words are full of hope (or rather “estel”, trust in Eru)

Originally posted by Child of the 7th age
I don't want to minimize the joy that is there in the ending. Indeed, one of the reasons I have trouble with some modern fiction is the underlying sense some authors convey that nothing has any intrinsic meaning. Instead, they point to a hollowness at the core of existence.

Once more, I agree very much with you!!

Strider tells the hobbits about the song of Tinuviel:

"It is a fair tale, though it is sad, as are all the tales of Middle-earth, and yet it may lift up your hearts"

"Lift up the heart" that is just the effect that reading the LotR has on the reader!

I also think the ending is rather realistic, in a way. It is not made sure what is really going to happen to Frodo, just as we don’t know what lies beyond the circles of the world. And the fact that the Elves, Ents, Dwarves, Woodwoses etc are all slowly going to vanish and only remain as a few misunderstood words in old poems and fairytales, and that Middle-earth and its magic will be replaced by the modern world is quite true and generates this “Heartracking sense of the vanished past” as Tolkien called it in a letter.

Originally posted by Dirigel quoting Child of the 7th age:

He did, because once the ship left the waters on the Straight Path, he died and went to heaven.

But Tolkien said explicitly:

from letter 181
The passage over Sea is not Death.

And I don’t agree with Davem’s opinion here:

What the post-LotR writings by JRRT have done is make his sojourn in the West a temporary thing for us, a transition period before he dies. This actually takes away the feeling that he has been rewarded for his sufferings on behalf of the people of Middle-earth. However long he got to spend in the West, he died. His time in the West is now seen (in Tolkien's words in one of the Letters) as a period in 'purgatory'. This effectively lessens the sense of 'completion' we feel when we read of his coming to Tol Eressea.

What I mean is, whether we think of Frodo's passage into the West as an allegory of his dying, or whether we see it as his going to the Earthly Paradise, the end of Frodo's story for us now is his death. He gets no 'reward'.

No reward? But look at what Tolkien wrote:

from letter 246:

Frodo was sent or allowed to pass over Sea to heal him - if that could be done, before he died. He would have eventually to "pass away": no mortal could, or can, abide for ever on earth, or within Time. So he went both to a purgatory and to a reward, for a while: a period of reflection and peace and a gaining of a truer understanding of his position in littleness and in greatness, spent still in Time amid the natural beauty of "Arda Unmarred", the Earth unspoiled by evil.

Bilbo went too. No doubt as a completion of the plan due to Gandalf himself. Gandalf had a very great affection for Bilbo. His companionship was really necessary for Frodo's sake - it is difficult to imagine a hobbit, even one who had been through Frodo's experiences, being really happy even in an earthly paradise, without a companion of his own kind, and Bilbo was the person that Frodo most loved.
But Bilbo also needed and deserved the favour on his own account. He bore still the mark of the Ring that needed to be finally erased: a trace of pride and personal possessivness.(...) As for reward for his part, it is difficult to feel that his lilfe would be complete without an experience of "pure Elvishness", and the opportunity of hearing the legends and histories in full, the fragments of which had so delighted him.

This feels very much like a reward to me! And the fact that he, as all mortals, will eventually die, doesn’t trouble me at all. Look at this quote:

from letter 325:
-As for Frodo or other mortals, they could only dwell in Aman for a limited time - whether brief or long. The Valar had neither the power nor the right to confer "immortality" upon them. Their sojorn was a "purgatory", but one of peace and healing and they would eventually pass away (die at their own desire and of free will) to destinations of which the Elves knew nothing.

So Frodo will lay down his life much in the same way as Aragorn did: trusting in Eru and knowing that he has fulfilled his life .
I will much rather believe in Tolkien's explantion than worry about the mysterious and depressing poem "the Seabell"!

originally quoted by Raynor:
Death as inevitable ending for Men was, apparently, a by-product of Melkor's influence on them

I thought death was "the gift of Iluvatar" and originally not meant as a punishment ?