Charlize Theron is pissed at Kristen Stewart over her affair with married director Rupert Sanders, whom they both worked with on Snow White and the Huntsman. Theron is close with Sanders' wife Liberty Ross.

"She is very tight with Liberty, has often socialized with the family over dinner and cannot believe Kristen has done this," an insider told RadarOnline.com. "When they were filming Snow White and the Huntsman, Charlize felt like an older sister to Kristen, and they were always sharing advice. Charlize confided to her new pal about her adoption plans. She even asked Kristen if she wanted to be her baby Jackson’s godmother—that was how close they were."

Perhaps they weren't close enough, though, because Stewart kept it from her that she was having an affair with Sanders.

"Charlize had no idea what was going on between Rupert and Kristen and now feels completely betrayed by the whole incident," says the insider. "It’s certainly left Charlize between a rock and a hard place, because she feels great sympathy for Liberty and the kids and yet, she has a sisterly love for Kristen."

[Radar Online]