Vivian enjoying Christian fucking her is not evidence that she enjoys humiliating Hutch. As I wrote previously, Christian has power over her, including sexual power over her. She is submitting to Christian because he is able to dominate her through manipulation and through sex. As far as Vivian being dumb, that is correct, but far more than just being dumb, she deludes herself. Just because someone does something completely illogical does not mean that their behavior is unbelievable. It is illogical, for example, for a woman whose husband beats her for decades, to believe he is going to change and stop beating her, but there are MILLIONS of women who think that. A delusion is when you believe something that is irrational. It usually happens when a person wants to believe something badly enough, like the example of the battered wife who tells herself her husband is going to change. Vivian was deluding herself when she told herself that Hutch might not know what she did. Christian was completely aware of this. That is one reason he made the comment about what he would do to a man who said he was going to sleep in the same bedroom as his wife. He was making a comment about how weak Hutch was, but he was also pointing out that Hutch had to know what was going to happen. In other words he was telling Vivian she was being irrational, but he did not care because he knew Vivian was wrapped around his finger. Christian is enjoying humiliating Hutch, but Vivian, at this point, is not. You have provided no evidence that she is enjoying Hutch's humiliation. Saying she enjoys the humiliation is not evidence she enjoys the humiliation. Saying she keeps doing it is not evidence she is enjoying it because she is being manipulated into doing it. There is no evidence from the dialogue, the body language, or facial expressions of Vivian that she is enjoying Hutch's humiliation. You simply want to believe that. You may get your wish in the future, but that is not the case right now.