I am humbled. The woman is responsible. We cannot know if they are intimated or not. It could be supposed. It doesn't matter if this woman slept with this friend or not; staying at his house and drinking with him all day and late at night is considered a betrayal to her husband. Plus, they went outdoors, hugged and kissed before they separated. The two protagonists of the cheating also provoked, developed, and proclaimed this relationship, this feeling of betrayal. The husband made a mistake, but he is only half guilty.