Kate Winslet and Sam Mendes always seemed to pe the perfect image of a happy, down-to-earth, well-rounded couple. So what led to their surprising split? Stage and screen actress Rebecca Hall may have the answer.

Read Kate Winslet and Sam Mendes Split

Friends of the couple say Mendes got a little too close to Rebecca for Kate’s comfort. Though sources don’t allege that Mendes cheated, he grew very close to the actress and collaborator over the past year, and Mendes turned to Hall for comfort when he was stressed about his marriage.

Mendes began working with Hall, a Cambridge-educated actress who starred in Woody Allen’s Vicky Cristina Barcelona, shortly after his marriage began to break down. Sources say the trouble began soon after Mendes directed Winslet in Revolutionary Road.

Meanwhile, Winslet’s Revolutionary Road costar and two-time onscreen love interest Leonardo DiCaprio is apparently helping the actress get through this troubled time. “Kate has always really adored Leo and feels like she can tell him anything,” a source told the Sun. “He's been a rock for her.”

As more details about the couple’s crumbling marriage leak, Winslet is vacationing in Mexico with her children, Mia and Joe, and actress Emma Thompson. (Daily Mail, Newser)

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