It is hard for people who don't have pain to understand what it is like to have chronic pain. So try to be patient with your wife. Maybe if you described it to her she could understand. I have fibromyalgia, so I know how you feel.
When she expects you to go with her to your mother's, did you explain to her that it is too hard for you? If you don't tell her, she wont know. Maybe you should sit down and explain to her that it is hard for you to do things around the house. But do try to keep moving as much as you can. If you don't, you are going to become weaker. So I would suggest short walks if you can do it.
Keep after you SSD and your workman's comp. They will fight to the very end, but you will win...
Good luck with your book. You must of had a very interesting job if your wife thinks you should write a book.
Take care,
Hugs, Karen