John Mayer Addresses Ex Jessica Simpson's Memoir: 'I've Heard Some Bits' but 'I Lived It'

John Mayer has responded to ex-girlfriend Jessica Simpson’s recent memoir Open Book, in which she candidly discussed their on-again-off-again relationship.

Speaking with good pal Andy Cohen via video chat on Wednesday’s episode of Watch What Happens Live, the musician — who recently made a “generous” donation to help purchase needed ventilators at his local Montana hospital — confirmed that he was aware of the release.

“I’ve heard about it. I’ve heard some bits,” Mayer, 42, said. “But as Pee Wee Herman says in Pee Wee’s Big Adventure before the movie of his life is about to play out at the end — he’s not watching the movie, and the reason he’s not watching the movie — he says, ‘I don’t have to watch it, Dottie, I lived it.’ And I think that’s prescient here.”

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In her memoir, Simpson, 39, said that she never felt like she could be herself with the singer-songwriter, whom she met in 2005 and began dating the following year.

Speaking with PEOPLE ahead of her memoir’s release, Simpson said that her relationship with Mayer had “control” over her. “He loved me in the way that he could and I loved that love for a very long time,” she said. “Too long. And I went back and forth with it for a long time.”

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Matt Baron/BEI/Shutterstock John Mayer and Jessica Simpson

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The pair ultimately called it quits in 2010 after Mayer referred to Simpson as “sexual napalm” during a Playboy interview, for which he has since publicly apologized.

“He thought that was what I wanted to be called. I was floored and embarrassed that my grandmother was actually gonna read that,” Simpson, who is now married to Eric Johnson, wrote in the memoir. “A woman and how they are in bed is not something that is ever talked about. It was shocking.”

The hardest part was learning Mayer had broken her trust. “He was the most loyal person on the planet and when I read that he wasn’t, that was it for me,” she says. “I erased his number. He made it easy for me to walk away.”

Although they are no longer in touch, Simpson says, “I know that he’s publicly apologized and I don’t want to take that away from him.”