Boromir, Theoden, Denethor all die. They may each have weaknesses and personal struggles, but none of them are evil.
Also Bilbo and Frodo leaving for the Undying Lands always felt like they died to me, leaving everything they knew behind without ever being able to see it again. Same with the Elves "fading" and slowly departing from Middle Earth, which I also interpret as an allegory of death (this being the closest they come to it from a mortal perspective).
Reading LotR always felt profoundly bittersweet to me, and that's one of the main reasons I love these books.