i have the same problem with letting go into sleep. one method i have used that helps is as i am laying waiting to drift off to sleep i consciously bring to mind everything i am worried or anxious about. then i say "yes, situation X, i give that to God, my Creator can worry about that while i am sleeping" then "oh person A? yes, that is God's problem too, i leave it in God's hands.." and so on, and so on, till i have run out of things to be worried about or i fall asleep. you might try it, it helps me.
then first thing in the morning, wake up and thank God for worrying about all the things you usually do.