I've been trough Depression, again, and notice that depression is kinda like carrying the One Ring:
-It's a heavy burden
-You have to carry it yourself
-You can't give it to anyone else without corrupting them, even if they can resist it
-You can't walk alone
-Friends find you wierd because you have the tendency to disapeer in the middle of a party.
-You can, in theory, just hide someone and forget about it, but it's praticly impossible to do
-On the outside it doesn't look that bad, but it's slowly twisting you on the inside...
-You tend to favor dark places, away from daylight and people, and rely on the same food day after day...
-Even if the situation is dark, bleak and that every odds seems agains you, some friends will always be at your side.