It's been a while since I've done one of these. Oops.
#9: Which song do you sing only when you’re alone? What memory does it bring back?
There are a handful of songs that fit this, though it's not so much "sing only when you're alone" as "play on repeat on iTunes."
Alanis Morissette's "Not as We." I found this one after it was played in an episode of House. The song was used in the episode titled "97 Seconds," during the scene where House contemplates sticking a knife in an electrical socket in order to see if there's anything "after" we die. I've always loved Alanis, even when I was in junior high and Jagged Little Pill came out and I didn't understand what half the songs were about, but knew taht she was awesome.
Evanescence's "My Immortal." This reminds me of my high school crush, and listening to it over and over and over when he left for Army basic training. Sigh.
Those are the two I can think of right now. There are undoubtedly others. Unfortunately, both of them are songs that remind me of sadness and loss.