A dog is a very social animal. They live and die in the wild with their pack. In your home, you are their fellow pack members and that means, when they are left alone as you go to work or run errands, they grow anxious and worried that you may not come back. However, just because a dog is anxious that you are leaving does not mean that they should react so strongly. From barking and whining to destructive behaviours like chewing, digging, and tearing, a dog with separation anxiety can be very hard to deal with.