I came to the realization that I was different. I didn’t want to hurt people, but I could, and when I did, there was something cathartic and liberating about it, especially because any collateral damage was almost always rectifiable. I know about guilt, and it doesn’t apply to me—I don’t carry the burden of it.

In Chapter 14, Stephen tells the story of killing Marvin, his younger cousin’s pet turtle, as an example of a time he understood that his emotions are not like most people’s, in the sense that he feels no guilt over hurting others. This aspect of Stephen’s character is central to the book. It explains his behavior toward the women he dates, including Lucy. He feels no guilt over infidelity and finds life more convenient with a girlfriend, so he uses his charm to convince them to stay with him, without feeling any dissonance between his words and his behavior. When his DUI arrest leads to rejections from top law schools, he feels only fury at the police officer who arrested him instead of regret for his own actions. Even Macy’s death is just a problem to be solved: Stephen’s only real concern is that being found complicit in her death would damage his ambitions. Stephen sees the world as ruled by “nature’s laws” and feels no shame in his amoral behavior toward others. 

People always talk about realizing they’re in love during the happy moments, but I think you realize it in the bad ones.

This quotation occurs in Chapter 21, when Stephen is back with Diana and Lucy is miserable and unable to move on from her relationship with him. The book continually explores the irrationality of love and Lucy's false belief that pain and love are inextricable. At this point in the book, a summer has passed since Stephen betrayed Lucy at the Hawaiian Luau by going home with Diana without explanation. Lucy is still angry and hurt at how he abandoned her at the party and has ignored her since. Nevertheless, she cannot stop thinking about him. When, at her friends’ insistence, she makes out with Topher, she feels no excitement, only regret that he isn’t like Stephen. Counterintuitively, Lucy believes that her misery is proof that she loves Stephen. Remaining in love with him despite his cruelty demonstrates the argument that for characters who are disconnected from their authentic self as Lucy was, love exists in the heart, not the rational mind.

As Stephen enveloped me, I suddenly understood the other piece of the truth—Stephen and I were the same. I was emotionally intelligent enough to know that Stephen was not good, not objectively, but if I stood face-to-face with myself in the truest light, I wasn’t, either.

Lucy comes to this realization in Chapter 41 when she is sleeping with Stephen, who has just explained that he will not be breaking up with Alice in June, as he had promised, but in August, since breaking up with her would mean losing his place to live in the city. This moment marks a turning point in Lucy’s character. For much of the book, she adopts a victim mentality, seeing herself as a good person betrayed by others, first by CJ and Gabe and later by Stephen. In this scene, Lucy recognizes that she, too, has behaved unkindly and selfishly toward people who love her unconditionally. Although she previously justified her behavior in her decision to steal Marilyn’s jewelry, in her ill-timed disposal of her high school boyfriend, Parker, and in her emotional coldness toward her father and Georgia, Lucy now realizes that her anger at CJ’s betrayal does not excuse her selfish behavior. This realization makes Lucy feel closer to Stephen as someone who is flawed as he is, rather than an innocent victim. This epiphany compels Lucy to begin questioning her moral degradation and to express guilt over her role in going behind Alice’s back with Stephen.