I've been fortunate in my life to not have too many instances yet where I have been ill for an extended period, but I do know that in those times, it was easy to become depressed. I think part of that, for me is about control - that powerless feeling when one's health is at least to a good degree out of one's hands.
I truly feel for you - I'm sure it is quite a struggle. I'm glad you have solid recovery skills to fall back on - I find they apply to all aspects of my life. I'd probably be working a gratitude list daily (probably multiple times a day) to make sure I focused on the good instead of the truly lousy health issues.
You sound like despite all that is going on in your life, you and your wife are handling things well - my good thoughts and prayers are with you! You aren't broken - you are just a different model than you were before - I hope you can make it the best yet!