"Kilkelly" - This song makes me cry. It tells the story of an emigrant from Ireland, through letters from his family back home. All we hear is the text of the letters he receives (we never hear his response), and it's just... so sad to me. The composer based it on actual letters he found, I believe (I don't remember the full story).
"I Don't Like Mondays" - by the Boomtown Rats.
I really like the melody, it's catchy. But, I didn't realize, until someone online pointed it out, that the song was actually based on an actual event (a shooting in 1979).
It's depressing enough that I'll put the rest in trigger quotes...
I need to listen to happier music!