I used to lie awake, toss and turn and grind my teeth in bed. I worried about what would lie ahead or what happened in the past. I used to over think a lot. There would be moments of respite, broken sleep, then I'd get up for the day, exhausted. I sleep soundly now.
Meditation had a lot to do with it. Meditation, twice a day - first thing in the morning and right before dinner. My mind puts worries into context, I'm humbled by past similar experiences, look to solutions and get on with it.