I recently went through the same thing. My dogs went to being around someone virtually 24/7 to me being gone for sometimes 4 hours at a time.
When I got my first dog, he was 7 and he had bad separation anxiety. His prior owners had several yorkies, so I don't think he was used to being alone, ever!! He would poo in the house if I left him inside to go mow the lawn even!! He would also pee everywhere!!
At first, I let him have full access to the house and he peed everywhere, so then I got him a belly band. This stopped him from peeing on things but I didn't like the idea of him wearing a belly band because a.)once he peed, he had to sit in a wet diaper until I got home and b.)I was afraid he'd get catch in on something and hurt himself....SO, I put him in a kennel.
He seemed to do better in a kennel but he still wasn't happy...so I started looking for a female dog to keep him company. I'd always heard you put males and females together instead of dogs of the same sex.
I couldn't find a female dog that i wanted to adopt, but after a LONG search, I found the sweetest little male. I was hesitant, because they were the same sex, but I gave it a shot and now they are best of friends...oh yea, and my older dogs separation anixety is pretty much gone!!
I also have a nanny cam so I can watch the boys while I am gone...but that is obviously more for my separation anxiety than theirs |