My wife and I got through it today. But man oh man, it was so, so hard. I'm crying right now as I type this, but I thought it might be good to get it out and tell someone. The vet got us in quickly this morning and it was taken care of very carefully and tactfully. We decided to stay with Max until he was gone. The vet who took care of this told us not to be concerned, but she cries every time she has to do this and indeed she did. She says the day she doesn't cry, is the day she stops doing it.
She warned us that Max could cry out and lose bodily functions, so to be prepared, but he just looked at us and was quiet as could be. It almost looked like he was finally happy to be out of pain. He passed away quietly and extremely peacefully. He didn't cry out or even utter a sound and passed within mere seconds.
It was indeed the hardest thing I've ever had to go through. I told my wife I never, ever, ever want to do that again. She then reminded me about our 13 year old cat. Hopefully he is with us for quite some time longer.
I can't believe the emptiness it leaves though losing a pet. You just never realize how you take for granted this loving animal who greets you at the door and lies by your feet and how excited this friend gets when you grab the leash for a walk. We're never going to get to do that again. Never going to see his excited face when we give him a bone he so loves to chew on for an hour.
Thanks to those who offered condolences and I feel for those that have gone through this, as we have. If you still have your dog, please give him or her a hug and remember how lucky you are.
RIP Max my friend. You were so loved and will truly be missed.
Edit: Thought I would post a pic for those that want to see our shaggy buddy...