About eight years ago, I began bicameral sleeping. It's insomnia with at twist. Trying not to wake the husband and kids, I started reading fanfic in that window when I was supposed to be sleeping. Then I started writing. It worked for years. Next time you can't sleep, get up, set a timer for fifteen minutes, then write. Noodle ideas. Jot notes for a character or setting. When the timer goes off, go back to bed and try again.

Eventually, I worked the waking time in the middle of the night down to two hours, and it helped tremendously. I also added an hour to each end of the sleep brackets, and that helped more.