AAAwww I am sorry we are all feeling your pain as we have all at one time or another gone through this.
We have always had 2 dogs, when our first went to the fields and fields where she could run free of pain our older boy was lost, he had aways had another 'playmate','Carly' our girl or fosters. Her leaving him left him in pieces, he stopped eating and would mope around and sleep ALOT for weeks. We as a family were not sure if we were ready for another dog and I knew we didn't want a puppy ~ so months later when Libby(our EM) found us we were unsure how our old man would feel about an adult coming into the house...he loved it. Being as that she was 3.5yrs it brought the spring back into his old bones and he looked and (I think) felt better than he had in a long time. Being as Libby outweighted Hoover by 100lbs we all knew who the boss was ~ skinny old man Hoover
Libby had always been around other dogs since she was a puppy, so the match was perfect for us. Hoover left us acouple weeks ago
and Libby hasn't been the same ~ she doesn't want to leave our side, when she goes out to potty I make her go out~ she cries/barks and wants right back in asap, she has lost weight, she was only with Hoover for 2yrs but in that time the bond grew strong she was very dependent on him he was her security blanket. We have changed up her day like other have said, I know we are not ready for another dog, I just hope she can bounce back to her old self with time.
How is your dog with others? Has he been exposed to puppies? Are you ready for another?
Wishing you all the luck, welcome to the best forum around, everyone is super helpful.