I feel your pain and we lost our dog Shadow last week on Nov 2nd. He would have been 17 years old in January so we have a lot to be thankful for however he was very healthy for his age and the vet expected him to live a few more years. So his passing was very unexpected and I would have gladly traded years off my life to keep him around longer. Every night when I go to bed I hope to see him in my dreams just so I can share one more moment with him.
At one point we had 3 dogs and now the house feels so empty without them. He was the first one we got and the last to pass. There are no words that can be said to make things better and while the memories will last a life time it just never feels the same. Our dogs meant the world to us and our lives revolved around them so even as time passes the void will never be filled.