My insomnia started when I couldn’t sleep because of DH when he was ill. I was always up half the night, changing bedding, calming him down etc. When absolute exhaustion overtook, and I did close my eyes my ears were still open. Only way I can describe it.
When he died I still laid awake listening for him and the habit continued.
Someone mentioned melatonin.
Oh my goodness, it works! And I’ve tried sleeping tablets from my GP, anti histamines, whiskey in hot milk, all sorts.
But I recommend trying melatonin, from Amazon it’s where I got mine.