Everyone else has given such good advice about resources for your husband, I thought I would offer something that might be helpful for you as your husband's partner. You are, after all, living with his PN as well.

There are two great articles you can find at this website:

Pain Treatment Topics

About midway down the page you will find the heading: Chronic & Intractable Pain. The two articles to look for are: Surviving a Loved One's Chronic Pain and Intractable Pain Patient's Handbook for Survival

You have found a great place for support and knowledge, and we are glad to have you here.