Sort of like you I have experienced periodically not being able to sleep through the night the last year. I’m a bit of a worry wart and if stressed about something I can’t sleep. I will sometimes wake up at 3 A.M. and if I can’t get back to sleep will get up. Usually the next night I will sleep at least 7 hours. I have never been one to take an afternoon nap but I think it would be a healthy thing to do.
I’ve heard drinking a glass of warm milk before bed would help one get more than twenty winks. Counting sheep doesn’t seem to work :)