insomnia

On and off my entire ("adult") life I've struggled with insomnia. Pretty much I think it's the stupidest affliction. I went to bed early tonight with the intention to get an early start tomorrow on thesis stuff. I was dozing off at 9:30ish so I just changed into my pjs, brushed my teeth, fed Chai and went to bed. But could I sleep? No. Instead I lay awake worrying about everything from depositing checks to booking a flight to Mexico. I need an on-off button for my brain.