I was just reading the info here about dysthymia. It sure sounds a lot like me, especially regarding therapy. The T I had this past fall and winter was so pushy for me to make changes instantly and would poo-poo me if I couldn't follow through or didn't do what he said exactly, that I got fed up with him and started canceling appointments.
I've got my fingers crossed that the lack of sleep is the major issue. I just feel like absolute crud when I'm not getting sleep. I can't function with work and then I get depressed because I'm not making enough money, I get tied to the computer for 12+ hours in order to reach daily goals, and then I have no time left for a life. Which leaves me more depressed, which makes it hard to sleep, which makes it harder to work, and on and on.
When I get restful sleep, I feel NORMAL

I have energy and direction and concentration. I get my work done in 6-8 hours and have time to actually spend time with other people and relax at the end of the day and even do some much-needed housework. I feel alive and useful. So maybe the sleep is causing the dysthymia, especially since I noticed it's gotten worse ever since I had the kids. Once they were sleeping through the night, then my H was bugging me for sex instead of letting me catch up on sleep. Then the marital problems started kicking in the more he'd pressure me to be something I couldn't be, and it just kept snowballing. Now all of the pressures are off of me, but I'm still not sleeping so I'm still in a constant state of sluggishness. I think that would make anyone depressed, to always feel like you're walking around in a fog, half awake, not being able to retain or comprehend easy info.
My doc at the County just didn't seem all that interested in tweaking meds. This one, who's a woman too, seems to really be ready to be aggressive with treatment, so I've got my fingers crossed that I'll have some improvements soon. If the Celexa/trazodone combo doesn't cut it, I guess I'll shell out the big bucks for Lexapro and see how that combo works, since the Lexapro does really help with my mood. I'm just hoping to keep treatment as cost effective as possible. Anyway, I'm rambling.