Women who have a higher socioeconomic background than their spouse tend to be judged by others as manipulative, pursue perfectionism, and care most about their reputation. This is why people tend to assume that stay-at-home dads must have lost their jobs due to their inability, or that their spouse is a workaholic, perfectionist, and controller. Furthermore, people easily conclude that those men are incompetent, so it is natural that they have a broken relationship with their spouse. This is why heteronormativity is applied to this movie because it depicts Amy as someone who complains about her helpless and aimless life with her husband and blames everything on her husband's incompetence, and Nick who overreacted to his wife and ended up abusing her to deny the fact that he is the one causing all this