This is quite the saga.   I have known people who are supposedly in constant pain;  one a father who actually broke his back moving a piece of furniture 25 or 30 years ago.  He now resorts to marijuana to kill the pain.    It so happens that his daughter is also a chronic sufferer.  She is massively overweight, never walks (due to her pain) and leads a very stationary existence.   
    Neither of them wants to even entertain the idea of yoga or walking or alternative, non-therapeutic drugs.   It's sad really.     Wish they, and other chronic sufferers, could read your story.