The birth, death, and resurrection of Jesus means that one day everything sad will come untrue.

It needs but one foe to breed a war, and those who have not swords can still die upon them.

The wolf that one hears is worse than the orc that one fears.

Those were happier days, when there was still close friendship at times between folk of different race, even between Dwarves and Elves.' It was not the fault of the Dwarves that the friendship waned,' said Gimli. I have not heard that it was the fault of the Elves,' said Legolas. I have heard both,' said Gandalf[.]

My friend, you had horses, and deed of arms, and the free fields; but she, being born in the body of a maid, had a spirit and courage at least the match of yours. Yet she was doomed to wait upon an old man, whom she loved as a father, and watch him falling into a mean dishonoured dotage; and her part seemed to her more ignoble than that of the staff he leaned on. -Gandalf to Eomer, of Eowyn

The world is full enough of hurts and mischances without wars to multiply them.

It's like in the great stories, Mr. Frodo. The ones that really mattered. Full of darkness and danger, they were. And sometimes you didn't want to know the end. Because how could the end be happy? How could the world go back to the way it was when so much bad had happened? But in the end, it's only a passing thing, this shadow. Even darkness must pass.