Life Sucks Sometimes, or, I really hate myself today

I'm having a crappy day. I woke up an hour early, my puppy is being neutered and I'm worried sick, it's about to pour rain, and my boss has been on my back all morning. My entire digestive system is acting up (no surprise there), every bone in my body aches, especially my old knee injury, and I just want to sleep for a week.

Mostly, I'm sick of living life this way. I work in an all grey cube in an all-grey room in an all grey building. I see the sun shine for about twenty minutes a day, on my way too and from work. When I'm lucky. I sometimes go days without speaking too another human being. I'm changing jobs in two weeks and going someplace that has windows, but I'm still going to be doing the same old crap as always. I don't want to be an engineer anymore; I hate it with a passion. Funny thing how hard I worked to finish my degree and yet how much I hate the work. I want to go back to school and do something else. I'd like to work with people. But I can't go back to school until I get some of these debts paid off.

And I couldn't do it anyway. My dysthymia tells me it's useless, I'm worthless and a complete failure of a human being. I'll never do anything good or great. I'll be dead before I'm fifty just like my parents and so what? My life is as grey as the cube I'm sitting in. And what's the point? It doesn't matter anyway. The world is going to hell in a handbasket. Nothing I say or do or think matters at all.

Part of me knows better. But that part of me is small and hard to hear. I've lived such a rotten existence for so much of my short life that it's hard to believe that anything else is real. When I feel like this I hardly have the strength to believe in God, whomever or whatever she may be. Much less anything else.
I want so bad just to be normal. Just so I could live like everyone else does. But that ain't gonna happen, no matter how much I want it or how hard I work to get it.