I have had a hard time falling asleep for years. I read an article on Pinterest about five years ago that surprised me, because it actually helped - a lot. I still use it.
It's simple. Close your eyes and slowly count backwards from 100. If your mind wanders or you lose your place because of intrusive thoughts, just start over.
I have also found it helps even more if I visualize the numbers as they enter my mind. It helps to keep intrusive thoughts from "taking over"!
It's worth a try. If you're like me, you've probably tried many things, including medications.