Dogs don’t understand the concept of breaking up the pack. They are loyal to the end. If you have doubts about this, go look up a few dog to dog reunions on youtube. And they WILL grieve once they realize the separation is not going to end. If they are elderly, it will age them faster & shorten their life; I had this happen to our lovely timid Corgi/Collie girl with my ex & myself & the rest of her tiny Chi pack members. For this reason, I would make every effort to handle the separation as much as possible like shared custody of minor children. I think everybody would be far happier. if you live in the same city, & it has a doggie daycare, you might enroll them both there, let the staff know the reason & ask them to accommodate together time, especially if your breakup was not cordial.
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