Enjoy your insomnia
Insomnia robs you of your night of sleep. That's your time. So ask yourself this question: if I had some time to do whatever I wanted, what would I do? Probably not lie in bed cursing the universe from preventing you sleeping, right?
Instead, we should enjoy our insomnia. Get up, read, watch TV, play video games. Ironically, because doing this will cause you to relax, you will find it easier to sleep later.