Oscar jokingly claims over the phone to be having an affair with Murray's wife, Murray replies, "I wish youwere having an affair with her. Then she wouldn't bother me all the time." Murray shows a general skepticism about marriage, saying, "Twelve years doesn't mean you're a happy couple. It just means you're a long couple." In contrast, Vinnie appears to have a happier marriage, frequently traveling with his wife. Unlike Oscar and Felix, the Pigeon sisters live together without major conflict, likely due to their similar personalities.

In the end, Simon offers insight by using the dynamics among the poker players to highlight Oscar and Felix's relationship. These players gather weekly and are well-acquainted, but their friendships aren't strained by the demands of living together over time. Simon skillfully portrays these relationships as potentially filled with conflict and tension due to differing personalities. For example, the quick-tempered Speed frequently appears ready to leave the group. Nevertheless, even Felix promises to attend the next poker night, asserting he won't "break up" the game because "marriages may come and go, but the game must go on."

Marriages survive through the compromises that emerge when inevitable conflicts arise. Oscar and Felix's story demonstrates that some disagreements are too substantial for compromise, yet they underscore the importance of compromise by showing subtle shifts in their personalities by the play's conclusion. Oscar's change is apparent when he takes a call from his ex-wife and mentions that he has completely paid his alimony. He says, "You don't have to thank me. I'm just doing what's right." His relationship with his ex-wife and son appears to be improving, as he has become a more responsible husband and father. Furthermore, he ends the play by telling the poker players, "watch your cigarettes, will you? This is my house, not a pig sty."

Felix's transformation is more mysterious. Moving in, even temporarily, with the Pigeon sisters, who are nearly strangers, is something Felix couldn't have done at the beginning of the play. But is he merely "loosening up" as Oscar suggested he should? Or is he contemplating a significant change and considering a romantic relationship with one or both sisters? As Felix packs his belongings in Oscar's apartment, he smiles at the poker players in a way that invites speculation. Will he try to organize the Pigeon sisters' lives as he did with Oscar's? It's uncertain, but it's apparent he has undergone some change, as he asks Murray to tell his wife, "if I sound different to her, it's because I'm not the same man she kicked out three weeks ago."

While the play's ending leaves the future of Oscar and Felix's relationship unclear, it seems unlikely they will live together again. Interestingly, the popular television series took a different path. In the TV sitcom version of The Odd Couple, Oscar and Felix remain roommates, having reached a level of mutual tolerance for each other's quirks. However, the series preserved much of the tension between the two characters to maintain the comedic conflicts similar to the play. This diverges from Simon's suggested ending but was essential to sustain a weekly comedy series.

The Odd Couple delves into the comedic yet poignant exploration of how ego and self-love can derail human relationships. It centers on Felix and Oscar, two individuals who have emerged from failed marriages only to find themselves embroiled in similar patterns of behavior that contributed to their initial downfalls. Both characters openly acknowledge their flaws, yet their overwhelming sense of self-love blinds them to the possibility that these very imperfections could have played a role in the dissolution of their marriages.

Felix, for instance, can readily list the bothersome qualities that prompted his wife, Frances, to part ways with him. However, his excessive ego prevents him from genuinely understanding or acknowledging Frances’ perspective. He sees himself as a superior cook and housekeeper, persisting in the belief that Frances’ decision to leave was both baseless and unjustified. Even when Felix claims to hate himself for his past actions, Oscar, his friend and roommate, challenges him with the assertion, “You don’t hate you. You love you. You think no one has problems like you.” This interaction underscores Felix's inability to learn from his past, as he repeats the same mistakes in his new living arrangement with Oscar.

Similarly, Oscar's life is steeped in self-centeredness, mirroring Felix’s issues. His sloppiness and insensitivity were central to the problems in his marriage to his former wife, Blanche. In a display of disregard for her needs, Oscar would wake Blanche in the dead of night to prepare food and showed little concern for their shared space, frequently damaging furniture with his carelessness. His tenth-anniversary gift to Blanche—a trip to a hockey game—further exemplifies his disregard for her interests. Oscar's existence is marked by a pursuit of self-indulgence, contrasting sharply with Felix's frugality.

Together, Felix and Oscar personify the pitfalls of unchecked ego and self-adoration within relationships. Their interactions highlight a profound truth: that without the willingness to set aside one's ego and genuinely consider the other's perspective, individuals are destined to repeat the same cycles of misunderstanding and disconnection.

Neil Simon's characters, Oscar and Felix, resonate with audiences through their authenticity and vulnerability, making them both endearing and relatable. Despite their apparent differences, Simon masterfully crafts these characters as ordinary individuals grappling with universal human experiences. Oscar, typically characterized by his carefree demeanor, occasionally allows his more sensitive side to emerge. His admission during a poker game that he enjoys bluffing parallels his real-life tendency to mask his true feelings. This facade crumbles further when he confesses his aversion to solitude, a feeling heightened by the echoing emptiness of his eight-room apartment—a poignant reminder of his recent divorce. "When you walk into eight empty rooms every night it hits you in the face like a wet glove," he reveals, exposing the rawness beneath his nonchalant exterior.

Similarly, Felix evokes empathy through his sincere concern for those he loves. His genuine affection for his wife, Frances, and his children is palpable, as is his earnest desire to help Oscar improve his life. Like the Pigeon sisters, audiences find themselves drawn to Felix’s earnestness, recognizing in him a man who earnestly wants to bring stability and comfort into the lives of those around him.

Within Neil Simon's The Odd Couple, a central theme emerges: the significance of compromise in relationships. By depicting the dynamic between Oscar and Felix as analogous to a marital union, Simon underscores the importance of achieving harmony through moderation and compromise. This partnership requires each individual to adapt their habits for the relationship to flourish; otherwise, it risks a "divorce," as portrayed twice in the narrative.

Throughout the play, both Oscar and Felix remain entrenched in their self-centered lifestyles, neither fully grasping the benefits of compromise. Their inability to adjust highlights the challenges of maintaining a harmonious relationship without mutual concessions. Despite the comedic failures of these characters, Simon champions the institution of marriage by highlighting the folly of selfish behavior. Through humor, he encourages audiences to reflect on their own potentially self-destructive tendencies.