I'm afraid this is a very common meno symptom and for me is the toughest to cope with. I believe there are various reasons why insomnia is an issue when meno hits, which includes disrupting the hormones to regulate the bodies natural sleep cycle - oestrogen is indeed the fuel that controls so much of our body. When I do sleep, I get horrid vivid dreams that leave me feeling awful the next morning.
I am now in the spare room as my husband adds to the disruption as he comes to bed late when I am either winding myself down or I have just dropped off to sleep so he wakes me, which then means I'm awake for hours. I also have to pee 2-4 times in the night and this disrupts my sleep and my husbands sleep. At least now I have control of my sleep environment and can move around in the bed to get the coolest place. If I know I have a busy day coming up, then I take a Nytol (the one with the antihistamine) which will usually ensure a reasonable night. I do Mindfulness which can help but it is often so difficult to switch the brain off.
You are not alone with this. When I had had a 3 year break from HRT in my early 50s, I then went back on HRT and the first thing I noticed was the improvement in my sleep. I'm 62 now, stopped HRt 2 years ago as the side effects of progesterone became to troublesome, so I'm just wading through without the oestrogen benefits as best I can. DG x