I work with the Animal Rescue and this is pretty common. The dog is experiencing separation anxiety. The dog has been abandoned once and now it wonders if the owner is coming back every time he leaves. We had a lab with a horrible case and it took her years to get over it. Some suggestions:
Start by leaving the dog alone for short periods. At first just go outside and come back in two or three minutes. That way the dog will start to realize that you aren't leaving it forever.
Crate Training. This works for some dogs. Our Ridgeback destroyed the crate, so it wasn't good for him, but some dogs feel more secure in a crate.
They make a drug for pet anti-anxiety called Clomicalm. It didn't work for our Lab, but many people found that it works very well.
I found that taking the dog for a long walk before we left her alone helped a lot.
What finally worked for our dog was getting another dog. We already had one dog and it didn't seem to help. When we got a third dog it helped the Lab calm down and the destruction eventually ended.
The real cure is a lot of love and patience. You don't know what the dog has been through.