Should've Said No by Taylor Swift is an emotionally charged country-pop song about betrayal and heartbreak. The song explores themes of infidelity, regret, and empowerment. Taylor Swift addresses a former lover who cheated on her, expressing her hurt and the realization that the relationship can no longer continue. Key moments in the song include the chorus, where she emphasizes the simplicity of the choices her partner should have made to avoid the pain caused. It's a powerful anthem of self-respect and moving on from a toxic relationship.