Have you noticed that when you are totally stressed, you snap easily? You yell something without thinking… and then realize to your horror that you gave the perfect imitation of one of your parents.
If you grew up in a family that didn’t know how to cope with stress, then your gut reaction is to act the same way they did. When stress builds up, your best thinking takes a back seat. Childhood memory grabs the wheel.
It doesn’t matter that you vowed to be completely different from your parents when you grew up. When you are under duress, the old voices take over. You might even wince as you hear yourself using the exact phrase and tone that you hated as a child or teen.