R2C, I'm very sorry to hear about your Dad AND your dog.
I think watching them lose hope is the hardest part emotionally. My Dad has loved to sing his whole life - he was in the church choir from small childhood until recently, was in the choir in high school, and then sang most of his adult life with barber shoppers - quartets or choruses or both. He recently "officially quit" the barber shoppers. I heard that he sort of stumbled getting on or off the risers. Thankfully a couple of the guys were right there and caught him, but I think his age related problems embarrassed him. I suspect he has cried buckets of tears ending that beloved hobby of his.
I am very sorry to hear that your Dad has lost hope of going back to work and also having surgery on his face if that was something important to him. It feels so helpless to sit by and watch this, and there is really nothing we can do to change it.
I lost a doggy to cancer in 2000 - that is also very difficult to get through. Sending you good, pain free sorts of vibes.......
DG