Britney Spears' ex-husband Jason Alexander slams Kevin Federline over his upcoming tell-all memoir

Britney Spears’ first ex-husband, Jason Alexander, has publicly criticized her second husband, Kevin Federline, over his forthcoming memoir, You Thought You Knew, accusing him of profiting from the pop star’s personal struggles. In a lengthy Instagram post shared on Tuesday, Alexander accused Federline of becoming "a millionaire off of her pain" and rewriting history at Spears' expense.

Alexander, who was married to Spears for just 55 hours in 2004, slammed Federline, 47, over the book’s portrayal of Spears, especially in relation to disturbing claims involving their sons Sean, 20, and Jayden, 19. An excerpt published by The New York Times alleges that Spears once stood in the boys' doorway holding a knife, a claim Federline says contributed to their decision to distance themselves from her during their teen years.

“Kevin, you don’t get to tell half the story,” Alexander wrote, stating that Federline was not a passive observer during Spears’ turbulent years, but an active participant. “You were partying right alongside her — the drugs, the alcohol, the chaos… you were there for all of it.”

He went on to criticize Federline for gaining financially and legally from Spears after their 2004–2007 marriage, noting he received full custody, child support, and maintained a lifestyle allegedly funded by her. Alexander accused Federline of now attempting to reframe himself as the responsible figure while distancing himself from the chaos.

“You became a millionaire off of her pain,” Alexander added, urging Federline to take accountability for his role in the narrative. “Don’t pretend you were the victim or the hero. Be real.”

In the memoir, Federline also details his concerns over Spears' mental health, especially leading up to her 2008 psychiatric hold and the start of her 13-year conservatorship. He recalls that period as “one of the hardest nights of my life,” admitting that he feared Spears’ behavior was escalating to an irreversible point.

In response, a representative for Spears told Us Weekly, “Once again Federline and others are profiting off her, and sadly it comes after child support has ended with Kevin.”

Federline maintains that his intent is not to attack Spears but to offer insight into their past for the sake of their sons, claiming, “I’ve only tried to help my sons have an incredible relationship with their mother.”