I have been one of the lucky ones who has rarely had any issue dropping off to sleep. I tell people that when I close my eyes, my computer shuts down ! ha ... .or sometimes when I think I am being funny, I tell them it is a lack of guilty conscience....LOL !
Of course through my life there has been the very rare night or two when I didn't drop off immediately. A few times it was hormone related. A few other times I wasn't quite sure, but I would force my mind to focus on on word, Jesus, silently saying His name over and over and seeing the spelling of it. The point is though, focusing on one thing, so the other things hush !.... and then I drift right off.
Maybe your blogging & etc is the same, focusing on one thing or subject, while everything else quiets away.
I feel lucky, because it seems as I have gotten older, more people than not are saying they have issues with sleep. I would be SO grumpy if it were an every night thing.