Here's an example of a story that happened to me. https://www.reddit.com/r/dwarffortress/comments/1mb0cw/the_s... Note: this story is in NO way embellished by me. Everything described there was actually fully simulated within the game.
My favorite horrible moment playing dwarf fortress came one day when one of my dwarves was unable to find a required bit of silk to finish the artifact she had swimming in her head.
She went crazy, presumably from the frustration, and took it out on a dwarf near her in a dining room. Soon thereafter my happy fort of approximately 100 dwarves was down to 10 or 12 dwarves, only 2 unwounded. There were bodies everywhere. Blood was tracking through the fortress.
Dwarves were wandering around, then seeing bodies, vomiting, going crazy, attacking each-other. It was terrible.
Long story short, we ended up with two battle-scarred, insane but deadened dwarves and a beautiful fortress for them to share. Cleaning the bodies out took both of them a couple of years. They'd haul for a while, stop to vomit, then keep hauling. Every so often at first immigrants would show up, and the entire group would go crazy looking at the carnage, and we'd be back down to my two dwarves.
I was trying to imagine what they might want or feel after all that, and decided it was likely they would have fixated on something, so they pulled all the gold and gems into a little room and made a throne room. The tougher dwarf was detailed to clean and haul bodies and bones, the other one just sat in his throne room, brooding.
Finally the tougher one died; he had some sort of minor injury I hadn't noticed, and we were down to one.
I can't remember exactly what happened, but I think that one was on his way to clean something up as the sole surviver, got too close to the river, and that, as they say was that. He drowned horribly, mercifully.
I occasionally think about the two dwarves just cleaning up the castle, slowly going insane, and when I do, I appreciate Toady's work, and I laugh. Then I feel guilty.
Reading this article and all these comments makes me want to get back into DF. I just hope I remember how to play. :p
Since then, I lost the link and forgot the terms to search for it! I'm so glad you reposted it. =)