It's another father-son play in which the son looks back and tries to understand Dad and forgive him for being such a jerk. Theirs is a classic bad marriage. She looks like the villainess and he looks like the long-suffering husband, until you notice how his avoidance is a form of aggression against this unwanted wife and son. When his family tries to grapple with him, he turns into a cloud of innocent incomprehension and leaves them clawing at the air.
Gene is potentially a great character.
Unlike them, his style is not pugnacious. He has dropped out. Unfortunately, O'Keefe's Gene is an oddly colorless performance. His amiability has no malevolent undertone. There doesn't seem to be enough there for his wife to hate and his son to feel guilty about.