PHOTOS: Kristen Stewart Cheats on Rob Pattinson With Married Director

Drama in the Twilight world...
Sources confirmed that Kristen Stewart cheated on her Twilight co-star and longtime boyfriend, Robert Pattinson, while filming her movie Snow White and the Huntsman. 
Kristen had a fling (not an affair) with Rupert Sanders, the directer of her new movie who is married with children. 
So how did these rumors start? The above photos were released to the tabloids which proved the scandal was true. 
PEOPLE talked with a source close to Kristen, "Kristen is absolutely devastated. It was a mistake and a complete lapse in judgment. She wasn't having an affair with Rupert," the source revealed. "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."
Robert Pattinson has yet to comment.