"The Last Day Of Our Acquaintance" is the eighteenth episode of the seventh season of One Tree Hill and the 148th produced episode of the series. It was broadcast on February 22, 2010. As Brooke angrily deals with Alex's tryst with Julian, Lydia's condition worsens, prompting Quinn and Haley to try to reconnect with Taylor. Clay is forced to deal with Katie's unsettling advances, and Nathan helps Jamie come to terms with Lydia's impending death.