It is possible that it might just turn around, but I would be betting against you...sorry. You have apparently gone on for some length of time needing sleep aids, and I can safely assume that prior to being prescribed those aids you were experiencing poor sleep for some time. So, all-in-all you have disordered sleep. The brain 'habituates' to pretty much any change by adapting. If you smoke, it stops making its own nicotinic receptor chemicals in its synapses. As long as you routinely up your serum levels of nicotine, it doesn't need to provide it itself. So this tells us that the brain adapts. It has adapted to your various prescriptions.
Have you ever investigated CBT or other forms of psychotherapy? Maybe you need to get something serious, and always pushed back down the hole, out into the open and deal with it. Literally get it behind you, not always in front of you. Your mind is active with....something. What is it?
Lastly, you're in excellent company if you're over 50 and can't sleep well. There are zillions of us. I can post how I manage to get two or three decent nights of sleep a week if you are interested, but there are no guarantees, not even for me. I can go two/three weeks with terrible sleep...just did.