Songwriter's Mind

Well, if I don't post in the next forty minutes, the wookies are gonna get me. So I thought I'd give ya'll a wee peek into my songwriting brain.
I haven't written a song in...well, here's something scary...I don't remember. The last few I wrote weren't very good. The more I get on a mental and emotional downward slide, the less I write. It seems I have to be at a "medium" depression level. I can't be too happy, or I lose the desperation that is apparently so important to my writing; I forget how entirely dependent I am.
But if I'm too low...then I can't get out of bed, can't make it to the piano, and I have no motivation. But somehow, I can't find the happy medium. I'm up, or I'm down, and I'm never level.
My songwriting, my school life, my relationships...they all seem to hinge on my mental health. And somehow I have to get that figured out.