Welcome to NeuroTalk:

I am sorry, however, it is under such painful circumstances.

I wonder about your PN symptoms. I suspect they were always there and just masked by your opiate therapy.

What happens with opiates over time, is that the glial cells which are the supporting cells in the brain, have been found to be active participants in the pain cycle. Over time they create inflammatory molecules that stimulate pain cells to make more receptors. Each day more involvement of the glial cells in the pain cycle is discovered.

So in essence when you discontinue a long course of pain therapy, you end up with MORE receptors than you started with.
This is thought to create more intense pain than you had before.

If you Google "glial cells pain" you'll find many complex biochemical medical papers in recent years. There are a few posts here about it even if you search "glial" on the index page.