I'm so sorry. I know that feeling and it's downright horrible. I've had days on end where I've just sat at the computer and laid in bed, getting up only to eat and go to the bathroom.
It's frustrating and I can't claim to fully understand your situation, but in the end what it comes down to is pushing yourself harder. Take that extra step, find something to do--get up, read, take another walk, do some cleaning (I find that useful for distraction), exercise w/ or w/o TV. Make food if you have the ingredients available. There are options.
It could also help to punch something like a pillow or rant. Blowing off steam will lift some weight from your shoulders.