PEOPLE.com broke the news, with an 'insider' telling them that Rob is "heartbroken and angry."
"I'm not sure they'll be able to recover from this," the source continues.
Yesterday Kristen issued a statement apologising for what she called a "momentary indescretion," before Rupert Sanders said sorry for hurting his wife and children.
"Kristen really loves Rob more than anything," says the snitch.
"He's all that matters to her right now."
Obviously not more than BONKING A MARRIED DIRECTOR. Probs.