Here are a few slower songs that I would suggest.
Black Sabbath-Changes (Volume 4)
Queensryche-Lady Wore Black (E.P.)
Queensryche-I Will Remember (Rage For Order)
*as well as the ones mentioned by DragonLord*
Savatage-Summer's Rain (Gutter Ballet)
Savatage-Sleep (Edge of Thorns)
*along with Dragonlord's picks*
Iron Maiden-Remember Tomorrow
NEVERMORE-The Hurting Words, Precognition, Sorrowed Man, Dreaming Neon Black, Believe In Nothing, Insignificant
I would also recommend Sebastian Bach-Most Powerful Man In The World (Bring 'Em Bach Alive) and George Jones-He Stopped Loving Her Today and If Drinking Don't Kill Me (George Jones Greatest Hits). These may not be Metal, but I like to listen to them when depressed and drinking Beer and/ or Whiskey.
There are many more I'm forgetting I'm sure of.
She screams from the alcove, I AM THE DOG !!!
ZANEX "THE DOG"