 and the dog becomes adjusted to you, and you go to leave, it's not the dog's fear necessarily of being left by himself. The dog's fear at that point is being totally abandoned, and you never coming back, because he's already been through this so many different times. As a behaviorist, studying for as many years as I've studied, the concept is that dogs learn through associative behavior. If the dog has associated in the past with previous people he lived with leaving and not coming back...