I do have theory that the reason why normal people don't have problems with falling asleep is basically they bore themselves to sleep every night (I mean... I met people who certainly had the effect on others, eh).

for example I don't get how can somebody not think of something all the time? what they do when they don't imagine things and create all kind of craziness and make mental witty notes about people they meet (or make up stories about them), etc. I mean HOW?