When have you been rejected? What was your immediate reaction? "Fight or Flight?"
The pain of rejection impacts the same part of the brain that registers physical pain.
The emotional response is a direct attack on your self-esteem.
So withdrawal from the social contact that created the situation seems the best way to handle it.
What is the cost of isolation? What happens to your life? The physical and emotional impact are devastating, because we all have an inner need for companionship and belonging. You have the key to unlocking that door of isolation. Every minute spent in anger and negative emotions is a minute lost of happiness and companionship.
Does your dog worry about you? They know you lead a stressful life. You are the most important person in their life. Do you recognize your dog in the pages of "Therapy for Humans, based on Dog's Advice" ? Is your dog smarter than your neighbor's dog (or your neighbor) ?