‘Grey’s Anatomy': The Many Hookups of Alex Karev
Izzie (Katherine Heigl)
Alex and Izzie had the longest relationship of the bunch. They flirted in Season 1 and then in Season 2 she finally accepted his offer for a date. Too bad he was cheating on her with the nurse, Olivia. Seasons 3 and 4 found the pair supporting each other in their other relationships (her – Denny; him – Rebecca/Ava). After finding out she had an inoperable brain tumor, the pair get married in Season 5. They got divorced in Season 6 after Izzie got fired and Heigl left the show.