You know the elephant man died while trying to sleep. He had to sit upright while sleeping because his head was so heavy it would snap his neck if he laid on his back. One night he wanted to try to sleep on his back like a normal person, and sure enough it snapped his neck and he died. Lucky him!
Yeah, insomnia gets me too. Having my mind wander leads to pretty dark thoughts and I get sad and angry. Very angry. I spend a lot of time thinking about torture whilst I try to initiate sleep.
The only way I've found around this madness is to stay up as late as possible, so that you'll pass out as soon as your head hits the pillow. This leads to really unpleasant and unpredictable sleeping patterns. But hey... better than the alternative.