If you haven't already, I'd suggest just seeing a doctor, and asking for something that will help you sleep. I was given 50mg Trazodone, and I feel like it's saved my life. It's not a controlled substance, so doctors and nurse practitioners hand it out like candy.
Now I get 8 hours of sleep a night, and most of the research I've dug up indicates it doesn't mess with your sleep architecture. There were some nasty side effects my first few weeks, but they seem to have faded over time.
I spent months and months obsessively reading everything I could about how to improve my sleep. Tried it all. Tried every OTC supplement even rumored to improve sleep. Nothing helped. And the more time I spent stressing about it, the worse it got. By the time I saw a doctor I'd probably gone two weeks straight averaging 2-3 hours of sleep a night. I felt like a shell of a human being.
Just asking for a pill might seem like an unhealthy cop out to some, but the improvement in my quality of life since doing so has been immeasurable since doing do.