I'm very sorry for your loss. May you and your wife weather this time and find another furry friend when the time is right.
I lost my best-ever pet - Casper, a flame point Siameese tomcat - before Christmas. My wife had shocked me with him fourteen years ago this Valentine's. All of our cats have been inside-only - and real pets - but he was special - thought he was a dog - call him and he came running! He was hacking up a hairball when he had a massive stroke. I held him for the long nearly two hours it took for him to pass. I was there when both of my parents passed - you are correct, my pet's loss was a greater shock in many ways. We have other cats - but he was mine - my wife and I elected to not have a tree for Christmas, he was that much a part of Christmas. Several days later, while closing his records at the vet, he mentioned he had a female tail-less orange tabby - and would test it (feline leukemia) and give it shots if I wanted. Her name is Delilah - and she has taken up some of Casper's mannerisms, almost as if she had part of his spirit. She will never be Casper - but she has eased a good bit of the pain. When the time is right - go rescue another furry friend... it'll help. It's hard to explain to others how this sixty year old man, a veteran - lots of 'life' experiences - was affected by the loss of 'just a pet'. I certainly feel your pain - and you have my sincere sympathies and best wishes.
John (aka 'Stainz')