Some choices that might be interesting in your situation are amitriptiline (or doxepin), mirtazapine or Nozinan. Amitriptiline or doxepin, formerly used as antidepressants, are now widely used for the treatment of chronic pain, migraines or insomnia. They can cause xerostomia as well, but may be better tolerated than Desyrel
Mirtazapine, while an interesting choice, would not be my first choice. While it is very effective at inducing sleep, it is also an antidepressant that can cause a lot of weight gain because it increases appetite
Nozinan is used to treat refractory insomnia. It is much less commonly prescribed for these types of conditions, but may be indicated when no other treatment works
In summary, you may want to ask your doctor for amitriptiline or doxepin. If it is ineffective or poorly tolerated, you could try mirtazapine. If it's still ineffective or poorly tolerated, Nozinan would be the preferred choice
Those would be the 4 choices I would see for your situation