1) "the realization that my life has changed for the worse in irreversible ways" - This is a dangerous perspective. Yes, life has changed, but if you focus on 'for the worse', you step onto a path that leads to depression in 90% of chronic pain patients. I instead focus on what I still can do. I might never be an athlete again, but I can walk. I can take short hikes in the mountains. I've changed my hobbies from an active collection of martial arts, biking, and hiking, into more sedate things like painting and woodworking. I celebrate staying active for half a day instead of dwelling on the fact that I used to be able to move all day. Much of your ability to adapt to chronic pain is mental, not physical, and this is exactly why CBT is recommended as a therapy - to help you to frame your life in positive, productive behaviors that keep you going in the right direction.
2) Everyone's pain is different. There is no single answer for how people deal with it (or fail to deal with it). This post sounded to me less like someone trying to communicate with their audience, and more like someone thinking it through for themselves. So while I had mixed reactions to the details of it all, I think the act of having put it together is likely a healthy move, so I appreciate the effort to have done so.