If you can't sleep, keep a pen and paper next to the bed. When you awaken, rather than lying awake worrying, write down all the things that come into your mind. Don't worry if you jump from one thought to another, just keep jotting down thoughts, ideas and worries. When you run out of things to write, you can assure yourself that you can let go of all those concerns for the night because they will be right there on the paper when you wake up.
A good friend of mine awakened each night for several years just before menopause, and would lie silently beside her husband in bed brimming with anger, although she didn't know at what. Finally she decided to get up in the night instead of just lying there. She would go to the kitchen and sit down and write out whatever came to her without even reading what she put down and without trying to make sense of any of it. After several weeks of this, she noticed that the anger seemed to become transmuted into new ideas. New plans and solutions to problems would come through her pen. For her, rising from her bed and writing built a bridge between the inner world, which was trying to make itself heard, and the outer, conscious, world in which she lived.
A good night's sleep, as Shakespeare knew, can "knit up the ravell'd sleeve of care."