Thanks, everybody Cyclothemia and get more sleep. Those are good ideas. I've been this way almost my whole life. Sometimes I have periods of constant depression for a couple of weeks, but usually it's just up and down once or twice per week. The difference between the two states is almost frightening. Earlier today I felt so bad I wondered if I had a physical illness like cancer instead of depression. Then suddenly all that depression disappears and I can think and do my work again and I start getting all kinds of ideas.

At least knowing the name "cyclothemia" gives me something to google. I might also mention this to my therapist.