I have no scientific input for your problem, but it is obvious that you do have a big problem. It may be that you have exhausted every option you have, other than perhaps finding a "doggie day care" so that the dog won't be left alone during the day. We have such options in our area. Perhaps you can find one for yourself. Call your local kennel and see if there is a possibility of a low cost option for you that way. Then your dog won't be left alone during the day.
Good luck.