I'm another who could not tolerate amitriptyline. (the low dose, normally used for bed-wetting in 7-year olds).
It put me on a different planet (my feet seemed to be miles away if I tried to look down at them) my guts went crazy, I got non-stop cystitis and I kept passing out. It took a long time for these effects to wear off after I stopped taking it - several weeks/months.
I didn't mind the side-effects too much when I was cheerful, (it was a bit like being drunk), but when I was in a bad mood or upset, it was unbearable.
But I do know of others (with ME) who swear by it.
How are you with alcohol? I know a lot of PWME can't drink; (I've been sober for 22 years and ain't about to start that again) but maybe a "nightcap" might help you?
I sometimes use a mix of valerian, passion flower, hops and lettuce extract, an OTC preparation that sometimes helps a bit.
Nothing much does help though. When I'm going through a really bad patch of insommnia, I find the only way to cope with it is to at least rest all night - to try not to let my brain get out-of-control fretting about not sleeping.
I do try a bit of self-hypnosis too.
Concentrate on breathing slowly and deeply in to a count of 10, hold it for a count of 10, then slowly breathe out to a countdown from10.
Do this 10 times, while staring at a point high up on the wall/ceiling, and DO NOT allow yourself to blink.
On the last breath out, you are allowed to shut your eyes when you get to the end, allow all your muscles to relax with the last breath out.
If it doesn't help, you can start at the beginning again. Or do it 100 times.
All the concentrating and counting helps to stop your brain racing.
Another thing I use to stop my brain racing is to go through the alphabet, listing 3 vegetables for every letter, or 5 boys' names or 5 girls' names, or 3, or 5, or even 10 of whatever takes your fancy.
Much sympathy. The worst of it is actually having to consciously exist while feeling utterly vile for up to 22 hours out of every 24. Sleep is such a joyous escape from it!