Insomnia is a gross feeder. It will nourish itself on any kind of thinking, including thinking about not thinking.
My life is quite physical anyway. When you are three-foot-six you kind of have to climb stuff now and again, and you find yourself in quite precarious situations just to manage in what is quite a big world.
Nothing can substitute for just plain hard work. I had to put in the time to get back. And it was a grind. It meant training and sweating every day. But I was completely committed to working out to prove to myself that I still could do it.