Kay should have realized what kind of man she was marrying, a man who had no choice, but to take control of his father's criminal empire. She loved Michael, but I understand that she didn't want to be with a mafia leader, as her life was threatened as is her childrens. How can she trust her husband as well? At the end of Godfather Part 1, Michael lied straight to her face, a relationship needs trust. Where's the trust?