Bad news, Twihards!

Despite the fact that Kristen Stewart and Robert Pattinson have been in an exclusive relationship for the past three years, the actress recently hooked up with her Snow White and the Huntsman director, and married father of two, Rupert Sanders, according to reports.

A source tells People mag:

    "Kristen is absolutely devastated. It was a mistake and a complete lapse in judgment. She wasn't having an affair with Rupert. It was just a fleeting moment that shouldn't have happened. She never meant to hurt anyone. She's a good person who just made a bad choice."

The Twilight stars were photographed just days ago looking lovey-dovey at Comic-Con, and the 26-year-old actor recently confessed to BlackBook: "It is true that Kristen has always done something to me that others haven’t."

A rep for Stewart had no comment, while Sanders' rep could not be reached, but it seemed the director only had eyes for his star at the Huntsman premiere in May!