I need doctor's advice on dealing with the emptiness from a dogs death?

Decide what it means: Only you can decide what the death of your pet means. You may decide, "Remember the good times", find a religious answer, think about how much better your dog's life was than the lives of most other dogs, find you answer in gratitude, or some other. If it is right, get another dog. It will not replace your past friend, but it will help. And perhaps a human love will enter your life.