Buffy The Vampire Slayer: 10 Worst Things Xander Ever Did
3. Cheating On Cordelia
Despite the early wobble, once Cordelia makes the rather brave decision to choose Xander over her friends, she is fully committed to their relationship. She throws herself into the Scooby Gang's adventures, and cares enough about Xander that she vows to remain by his side, even when she briefly believes that he has been turned into a Fish Monster in the episode Go Fish.
Unfortunately, Xander fails to show Cordy the same respect or loyalty. In Season Three, Willow and Xander embark on a brief affair, while both are still in relationships. While Willow expresses at least some guilt for the full duration of the cheating, Xander only appears truly guilty once the pair are caught.
The situation gains extra layers when rewatched through a modern lens. Willow had loved Xander for years, and yet Xander only took an interest in her once she was in a relationship. Two relationships were almost destroyed because Xander wanted something he could no longer have.