Chapter 18 details Rizal's disappointments in Madrid from 1890-91, including the infidelity of his beloved Leonor Rivera, who announced her engagement to another man. A rivalry developed between Rizal and Del Pilar, leading to divisions among Filipinos in Madrid during the election for a new leader of their association. Ultimately, Rizal decided to leave Madrid for Brussels, expressing a desire to finish his second novel and practice medicine in Hong Kong.