Unemployed-bored-bummed and useless blues

What is it about depression that makes one so endlessly tired? I knew a girl my freshman year of college who slept 16 hours a day. We eventually staged an intervention. Or maybe it's not always physical exhaustion but mental. I remember lying on the couch in my college house once, staring at the ceiling. My roommate came in.
"Oh, are you taking a nap?"
"No."
"Do you want me to turn the TV on?"
"No."
Eventually she covered me with a blanket and turned off all the lights. This amused me so much I was actually able to get up again 2 hours later.
Mostly it's the brain fuzz that bothers me. I picked up my phone tonight without knowing why. I stared at it for a full 10 seconds before I realized it was ringing. It's taken me 2 hours to write this.
There are two strategies I have when faced with depression.
#1 Distract yourself
Go drinking (not endorsed by this company), call someone, put on hideous makeup, eat nauseating amounts of chocolate. Yu Cheung, my wise Chinese mentor, calls these things "state modulators," a real term for dealing with the mentally ill. Often people with brain damage send themselves into fits. You cannot talk them out of it and if you wait it out, it sometimes gets worse. Even if you find what set them off and make it stop, it's too late, their mind is already in that fit. So you use a trigger: food, a smell, cherry chapstick, music, to literally modify their state. Works the same way with the depressed. We're going to Great America on Sunday. Riding roller coasters should do it for me.
#2 Ride it out (aka Give In)
Know that it will end someday. This is the most important part. Understand that you will not pay any bills, clean your house or function properly for the rest of the day and accept that. Get into bed. Turn off lights. Pull a blanket over your head. Cry, if necessary, or drink until you pass out. Often #2 is used only after #1 fails. It helps if you stop showering and answering your phone. You only eat food that is already in your fridge. Never mind cooking or scraping off the mold. At this point your sense of humor will dessert you entirely, as will your ability to, um...