Harry Potter.

You and Harry have been a couple since second year. It bothered you that he was so close to Ginny, as you knew how Ginny felt about him; he always promised and swore that he saw her as a little sister. Until one day, you decided not to go to one of the many parties held in the common rooms, choosing instead to study for the Potions exam. Harry, however, did go. The next day, as you walked through the corridors, you heard rumors that Harry and Ginny had spent the entire party together and were kissing throughout the night. Hearing that broke your heart, but you preferred to confront him first. You went to Harry's room, where he was still asleep.