I have no knowledge of Ambien, but am entering my 25th year as a member of the Chronic Pain Club. I am always sorry to hear of another member.
The first (and often heard) word of your post which jumped out at me was 'Miserable'. Yes, the daily, grinding pain, disturbed sleep and other issues make us miserable, but this rapidly spirals to Depression. Are you taking steps and getting the support at home to avoid this?
Secondly, you mention Ibruprofen and your G.I. tract. Are you taking anything like Lanzoprazole for it's protective properties?
Being in England I rarely see, and find it hard to understand the culture of 'med-seeking'. I assume it happens, but when your body has been smashed up a bit and you have had Neurological Hypersensitivity for 25 years you take whatever may give relief - however slight. I'm sorry some of your Doctors seem to look on genuine patients this way.
I hope you find the relief we all crave, but clearly Ambien and Ibruprofen do not work. Would it not be better to take a stronger prescription med that takes away more of the pain, protects your G.I . Tract and doesn't leave you miserable?
Whatever you want I am always here for support.

Dave.