Have you considered using over the counter sleep aids containing diphenhydramine or melatonin? I use these kinds of things occasionally. I've never had insomnia the way you are having it so I don't think this will fix the problem, whatever it may be, but it may provide some relief while you try to figure it out.

I'd also like to ask what's keeping you awake? Is there something going on in your life? I usually can't sleep when something is bothering me or when there is something I need to take care of urgently.