"Natalie is officially pulling the plug on her marriage," a source claimed of Portman, who married the ballet performer in 2011. "She really tried forgiving Benjamin — the last thing she imagined in her life was a divorce — but she could not get past the betrayal. Natalie finally decided that she couldn’t be married to Benjamin anymore."
"They went to counseling, and at one point, Natalie thought she could make it work for the children's sake," the insider revealed. "She desperately wanted to keep her family together, but at the end of the day, the trust that she and Benjamin had shared was irrevocably broken."
The May December actress and Millepied, who share children Aleph, 12, and Amalia, 6, separated last year after the choreographer engaged in a secret romance with Camille Étienne, 25.
"She was in shock when this all came out," the insider claimed. "It blindsided her and she didn't want to make any rash decisions, but she's now having second thoughts."
"He’s not going out without her these days — every night is date night while he gets back in her good graces," the source noted. "Her friends are all hoping he’s going to stick to his word and stay loyal. It’s the least Natalie deserves.”
"After news of his affair came out, they've been trying to work on their marriage but are currently on the outs," a second insider added. "Natalie believes Benjamin's affair was a brief and stupid liaison that means nothing to him."
However, the affair was too much for Portman to bear. "It's starting to look like she can't get past the betrayal," the insider said. "She hasn't come out and said she's leaving him. But a lot of people suspect that's where this is heading. It's not looking great."
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"There were long periods where Benjamin was effectively a single parent while Natalie was away making movies," the insider alleged. "Natalie gave him a lot of freedom to do as he pleased because she thought she could trust him."
Although Millepied claimed it "was short-lived and it is over," one source said, another claimed, "there is a lot that Ben is leaving out" about the relationship.
Life & Style spoke to sources close to Portman.