Nina and Ian, who were dating for more than three years before splitting in May last year, were awarded the 'Best Chemistry' gong at the ceremony for their characters Elena Gilbert and Damon Salvatore, who are lovers in the US vampire drama.
Once on stage to accept the award, Ian, 35, said: "This is crazy. Can you believe this is almost five years in the making?"
Nina replied: "You're right, yeah. But you know what's crazier though, Ian? At the beginning of the show, Elena actually hated Damon."
After a bit of banter back and forth, in which they outlined their characters' blossoming romance, Ian continued: "And then she fell in love with me."
Ian then explained that they began dating outside of the show, before Nina told the audience: "Then we broke up in real life."
They really did recall their entire romantic history in public!
Ian then added: "And yet our characters are still dating on the show."
Laughing with the crowds, Nina replied: "It's a good thing it's not awkward."
Proving that they are still the best of friends despite their break up, Ian even celebrated Nina's 25th birthday with her last night.
In a photo posted by the show's screenwriter Kevin Williamson, Ian was pictured celebrating Nina's birthday along with Julianne Hough.
Taking to Twitter, he said: "Happy Birthday @ninadobrev!!! The world loves you! We all do ;) Enjoy the moment, enjoy the day, enjoy the year!"
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