have you tried all the tips for sleeping well that you can find both in this thread and on the internet.
for example:
Tips for Sleeping well
1.Stick to a consistent sleep schedule and routine. Go to bed at the same time each night and wake up at the same time each morning. A set sleep routine will "train" you to fall asleep and wake up more easily.
2.Use the bed only for sleep and sex.
3.Cut down on caffeine. For some people, a single cup of coffee in the morning means a sleepless night. Caffeine can also increase the need to urinate during the night.
4.Be physically active. Regular aerobic exercise like walking, running, or swimming provides three important sleep benefits: you'll fall asleep faster, attain a higher percentage of restorative deep sleep, and awaken less often during the night.
5.Limit daytime naps. Prolonged napping can disrupt your natural sleep cycle and prevent you from feeling tired enough to fall asleep.
6.If you use tobacco in any form, quit. Nicotine makes it harder to fall asleep.
7.Use alcohol cautiously. Alcohol depresses the nervous system, so a nightcap may help some people fall asleep. But this effect disappears after a few hours and may even lead to waking up throughout the night. Alcohol can also worsen snoring and other sleep breathing problems.
8.Improve your sleep surroundings. Remove the television, telephone, and any other devices from the bedroom. This reinforces the idea that this room is meant for sleeping. An ideal environment is quiet, dark, and relatively cool, with a comfortable bed and minimal clutter.
9.If you're still awake after about 20 minutes in bed, get up and read awhile to relax. Otherwise, you'll set yourself up for tossing and turning.
10.Try to avoid taking sleeping pills. If you do take a prescription sleep medicine, work with your doctor to use it effectively and for as short a time as possible.
I keep a file of these. Do not know where this one came from. I have a relaxation tape that one can listen to whilst drinking a cammomile herb tea. If I take a tablet like Nytol then the next night I take a vitamin tablet following the same routine and that helps work like a placebo etc.
Good luck. An thank you to the contributor for the advice on Nytol and Dementia.