It is great that you've been able to avoid Opioids as they really are quite dangerous, specially if ending up depending on them ... There was an article in the Sunday Paper about the reliance of people on Opioids - with bad outcomes :(
Maybe consider having a chat with your specialist/GP about the possible use of Medicinal Cannabis Oil as it is 100% legal now and can help with side effects of chemo too. I've been using it for a few years now & it really helps ME with sleeping. I HATE it when I can't fall asleep!! I take it only at night now, half an hour before I go to bed (less than 1ml) and it really helps me nod off & stay asleep. If I forget to use it - I am awake on & off ALL night & it is a real pain in the proverbial! Depending on the strength, it can also take the edge off pain too ... so a win/win.
Take care xx