And it seems they are getting some third-party help in the shape of Kristen's mom, Jules, who is devastated about what happened.
"Jules is the glue that's keeping Kristen and Rob together," a source told RadarOnline. "It ripped her heart in two when she saw those pictures of Kristen in a compromising situation with Rupert - and she couldn't believe what her daughter had done."
"As far as Jules was concerned, Kristen's relationship with Robert was a match made in heaven and she adored him like he was her own son. At first, she struggled to understand why Kristen wanted to cheat on him.
"But Kristen's young and Jules knows mistakes will happen - so she supported her daughter's efforts to win Robert back.
"She has been speaking with Robert, re-iterating Kristen's pleas for another chance and is trying to help build up trust between the pair. It is early days - but if this reconciliation can bring Robert and Kristen back together, they'll have Jules to thank."
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