Sorry to hear of your loss man! That's tough for sure. I know a little bit of how that is, though always with cats but not dogs. I had a special cat growing up and it was tough to watch her fall apart and I got to snuggle with her in her last day before she gave up that evening.
One of the powerful quotes that I saw recently that moved me was something along the lines of "A dog to us is but a short time in our world, competing with other things but to a dog we are their world." I may have butchered it but I think you get the point. We have lots of things in our lives, including a dog but often the dog mainly has us in their lives. I want to get a dog one day but I don't know if I'm prepared for the eventual heartbreak when they leave the world. It's something we have to deal with for sure but it's a difficult one.