Robert Pattinson accuses Kristen Stewart of another affair

The Kristen Stewart cheating scandal has taken another twist, with new reports claiming that her estranged boyfriend Robert Pattinson thinks she's having another affair.

According to a Radar Online source, the 26-year-old actor is suspicious about Kristen's relationship with film producer friend Giovanni Agnelli, who she is currently staying with in Los Angeles.

"Rob knows Agnelli and has been calling him a lot since Kristen has been there," an insider told Radar.

"He wants to know why Kristen is staying there at his house. He is super angry now and has accused Giovanni of sleeping with Kristen too."

The source added that Rob called Giovanni at four in the morning on Sunday "threatening him if he has been sleeping with Kristen".

"Rob is beside himself over Kristen's betrayal. No one has ever seen him like this," the source said.

No one from Kristen and Giovanni's side has commented on the fresh allegations, but Giovanni has been actively defending Kristen on Twitter over the past fortnight.

"The spin that keeps growing on this story is staggering. There was NO on set affair. Stop printing LIES," he tweeted on Friday, blasting reports Kristen started seeing Snow White director Rupert Sanders on the set of the film.

Giovanni, the producer of Kristen's 2010 independent drama Welcome to the Rileys, has been "fielding all [Kristen's] calls via her cell phone and vetting who she gets to speak to, so not many people can get through to her right now," Radar reports.

So how is Kristen holding up amid all the craziness? She's apparently in tears all the time, and has a few other heartbreak habits.

"Kristen hasn't showered or changed or washed her hair in several days," the Radar source said. "She is laying around in her T-shirt and shorts and eating ice cream. She really wants to believe that she can win back Rob, but I think deep down she knows that isn't the case."

No showers? Come on K-Stew, get it together!

Whether the above is true or not, R-Pattz doesn't seem to be letting on about his troubles, making a low-key appearance with friends at "cowboy dance and music club" The Deer Lodge in Ojai, California on Friday night.

"He wasn't moping and the girls were definitely just his friends," an onlooker said.

Rob's first real public appearance since the saga will be on August 13 at the New York premiere of his indie thriller Cosmopolis. Kristen definitely won't be attending — Rob has reportedly banned her from the event, and security staff have been told not to allow her on the red carpet or at the after party, Radar reports.

Movie bosses are worried the pair's personal dramas will distract from the hard-hitting David Cronenberg film. No ... really?

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