I’m visiting this site because of a similar situation you described. I had to put my 15-year-old dog to sleep yesterday and my heart is broken. She had heart and kidney problems, but was doing ok until she took a very quick turn for the worse and couldn’t breathe. A chest X-ray showed cancer and she couldn’t be helped. The grief is intense. I’ve been crying all the time and can’t sleep or eat. It all happened so quickly. I’m sorry you had to experience such an awful event, but you’re not alone in your grief. We will never forget our beloved fur-babies, but I hope for both of us our pain will subside with time.