Just carrying a normal work load was never good enough. You had to do more to avoid the wrath of the alcoholic. One little slip up and the alcoholic might explode into anger. That deep-seeded fear can carry over into adulthood. Things never turned out the was the were planned.
People can become addicted to excitement.
There's always that nagging feeling that you were somehow responsible for the alcoholic's drinking. The authority figures in your childhood were probably abusive. You expect the same from all authority figures. When the alcoholic became angry, it usually meant something extreme was about to happen. You grew up with someone who was an expert at controlling and manipulating everyone around them.