The hot romance between Twilight co-stars Robert Pattinson and Kristen Stewart is already cooling down. 

Robert spent months trying to date Kristen, 19, even while she was still seeing her boyfriend of five years, Michael Angarano. When the couple finally got together, they denied they were dating but have regularly been spotted in public over the past few months. But now the two seem to have grown tired of each other. Perhaps working together and then reportedly sharing a suite at the Sheraton hotel in Vancouver while they shoot the third Twilight film, Eclipse, has been a little too much of a good thing.

“It was really exciting for her to sneak around her boyfriend and even the press, but once they became hot and heavy and able to be more public about it, Kristen started missing her ex and Robert is missing dating other women,’’ a friend tells BettyConfidential.