"When X, a polarizing and elusive artist, drops dead in her office, her grieving wife sets out to uncover the truth of X’s life," Portman wrote in her caption. "Part narrative fiction, part fake biography — Catherine Lacey’s Biography of X already feels wholly original and I can’t wait to discuss with you all. #JuneBookPick."
The Harvard alum's comments section was flooded by protective fans wondering why she is still married to Benjamin Millepied. One user wrote, "Why bother working it out with a cheater?" Another added, "She looks unhappy in all these book photos."
Despite followers' disappointment, friends of the couple claimed the pair aren't ready to go their separate ways just yet.
"They have not split and are trying to work things out," an insider told a publication. "Ben is doing everything he can to get Natalie to forgive him. He loves her and their family."
"She is incredibly private," they added. "Her biggest focus right now is protecting the kids."
The choreographer's extramarital relationship was revealed by a French magazine. "In early March, the star of the Star Wars saga discovered that her husband was having an affair with a young woman," the magazine claimed. Voici published several photos of Millepied and 25-year-old activist Camille Étienne.
- Natalie Portman and Benjamin Millepied Reunite at Women's World Cup After Actress Was 'Blindsided' by Shocking Affair
- Natalie Portman 'Blindsided' by Husband's Affair: 'She Was in Shock When This All Came Out'
- Natalie Portman 'Tried to Forgive' Her Cheating Husband But the 'Betrayal Was Too Deep': Source
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OK! previously reported the ballet dancer's romance with the environmentalist wasn't significant for Millepied.
"It was short-lived and it is over," a source close to the couple noted of his tryst. "He knows he made an enormous mistake and he is doing all he can to get Natalie to forgive him and keep their family together."
The pair met while filming the 2010 movie Black Swan, and Portman previously discussed the beginning of their courtship.
"I met my husband on it, so I think I was in, like, dreamland," she said of the Oscar-winning film during a 2018 interview. "He was teaching me to dance. You know, one of those romantic [stories] … It was definitely exciting and fun. It was beautiful. I don't know about instant. It was like I really got to know him and that was when it seemed like, 'Oh this is the person.'"
Sources spoke to Page Six.