Karyn Garvin has written a book , Separation Anxiety versus Containment Phobia, to help those with destructive, anxious, can’t be left at home alone dogs.
Following on my mindfulness article, I like how she suggests that your thoughts may be contributing to the problem. You love your dog so much that you are worried what is happening while you are away. I agree with Karyn that our dogs can sense our state even from long distances. We have heard of the studies where dogs exhibited welcome behaviors when their parents boarded a plane to come home.
Remembering that our animals can “hear” and sense our moods from a great distance is very important. When you are out of town you can regularly talk with your animals and tell them when you are coming home. In a non-anxious way you can do this for trips to the store. When your pet is critically or terminally ill, I still say to not show grief when you are with them (go for a walk). For years I have encouraged you to do the personal growth work needed to live day by day and not grieve at all, because they can hear you at a distance.
Karyn does give many good approaches that I have seen work for separation anxiety and destructiveness – accustom them to your leaving, not make a big deal of leaving OR returning, never chastise for destruction, etc. She also posits a new interpretation for these behaviors – Containment Phobia. If this is the problem, different strategies are needed in addition to the ones above. It may be as simple as putting in a doggy door and an electronic fence in addition to a regular fence. It may need a more major change in the house, but once done you are finished.
I do not agree with all of her suggestions, but they may be needed occasionally (muzzles, bark collars,etc). As always, do not think every expert is always right. Use your common sense and multiple references to make your own decisions. Then test them out on your dog. If your dog is happy and energetic and does not develop any of the early warning signs of illness, then you have reached a good solution.
I do like her reminder that when you have an escape artist, you should microchip. On our holistic list serves we discuss the potential harm of microchipping, and have never come to a consensus. We agree to minimize vaccines dramatically, but some feel chips are fine, some do not. You need to pay attention to any differences after the chip is in. In your case, the benefit probably outweighs the risk.
William Campbell, in Behavior Problems in Dogs (1975) is another great resource book. He gives a list of things that frustrate dogs causing them to develop destructiveness or other problem behaviors. Karyn goes into details for each item on his list, including ones like scolding, owner dislike of dog, changes, boredom, a stresses owner, physiological problems and more.
Though Karyn does not mention the many holistic aids to having a well behaved dog, she does suggest them for thunderstorm phobias along with TTouch shirts.