This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / A Scanner Darkly
Tear Jerker: The ending, but also the author's note as he memorializes his friends who died or suffered catastrophic organ/brain damage due to drugs.
In memoriam. These were comrades whom I had; there are no better. They remain in my mind, and the enemy will never be forgiven. The "enemy" was their mistake in playing. Let them play again, in some other way, and let them be happy.
Including himself, as he learned prior to writing it that his history of drug abuse had irreparably damaged his health. He died prematurely in 1982, just after Blade Runner was released, based on his 1968 novel Do Androids Dream of Electric Sheep?, a project he'd approved but didn't live to see become a cult classic.