"Oasis" by Amanda Palmer
Far as I'm concerned, you can't beat a peppy pop song about deeply, deeply depressing subject matter; stuff like, for example, Third Eye Blind's immortal classic, "Semi-Charmed Life," which was about crystal meth addiction, or "Burnin' Up" by The Jonas Brothers, which is about watching a lover die slowly from colon cancer (it's subtle, but it's there).
In that vein, I'd love for you to check out this little slice o' magic from Dresden Dolls frontwoman Amanda Palmer's solo album; it's insanely catchy and it's about having to get an abortion after being raped. That's entertainment, folks!
NOTE: Video NSFW if your work frowns on representations of rape and abortion played for laughs.
2ND NOTE: Tip of the hat to long-time friend of ZFS! Carly for directing me towards this awesome, awesome song, which I haven't yet been able to get out of my head with even the most potent of pharmapsychological drugs.