In response, a spokesperson for Bill Gates pushed back on the new biography “Billionaire, Nerd, Savior, King,” calling it “sensationalized”

Melinda French Gates; Bill Gates

(L-R) Melinda French Gates, Bill Gates. Photo: Christian Liewig – Corbis/Getty; Hollie Adams/Bloomberg via Getty

Since her divorce from Bill Gates in 2021, Melinda French Gates has spoken about living life on her own terms, using her voice — and fortune — in any way she chooses.

But that was something she sometimes struggled with while married to one of the most influential men in the world, a new book claims.

An unauthorized biography by New York Times finance editor Anupreeta Das, Billionaire, Nerd, Savior, King: Bill Gates and His Quest to Shape Our World, purports to shed light on some of the problems that were brewing behind the scenes for the former philanthropist power couple.

When Bill and Melinda started their eponymous foundation in 2000 — which she recently left — he was already incredibly famous and successful while the world knew little about Melinda, who lived life largely out of the spotlight, according to Das, who has covered the Microsoft co-founder for years and said she conducted “hundreds of interviews” for the new book.

Although Melinda, 60, initially “largely remained a presence by her husband’s side,” Das writes that she “always envisioned a bigger role for herself at the foundation” — and over the years, she began doing more public work on the charitable organization’s behalf.

“The two portrayed themselves as equal partners,” Das writes, “but it was clear that [Bill] drove the foundation’s direction and priorities, and that he was its chief spokesman.”

Billionaire, Nerd, Savior, King book cover

Cover of “Billionaire, Nerd, Savior, King: Bill Gates and His Quest to Shape the World.simon & schuster

As the foundation’s influence grew, Melinda continued to work on building her public profile — and a person who worked closely with her described Melinda as being “very interested in being seen as Bill’s equal,” per the book.

“She gradually felt her way around the chaotic belly of the foundation, scouting out a role for herself and potential perches she could call her own,” Das writes, noting that around 2010, Melinda began pushing for the foundation to work toward advocating for “women’s rights and empowerment.”

However, as Melinda found her place, according to the book, “she had to assert herself repeatedly” to employees who were “used to reporting only to” Bill, 68, who also had to adjust, in Das’ telling.

“Sometimes, he would cut her off too, and she would sit quietly, fuming. At other times, when he launched into a topic and threatened to go on for hours, French Gates would reel him in, saying ‘Bill, I think they get it,’ ” Das writes.

Melinda French Gates, Bill Gates

Melinda French Gates; Bill Gates. SXSW/Getty; Sven Hoppe/picture alliance via Getty

As Das pointed out, Melinda herself spoke about her desire, and struggles, to find her place in her 2019 book, The Moment of Lift.

“I’ve been trying to find my voice as I’ve been speaking next to Bill … and that can make it hard to be heard,” she wrote then.

In response to Das’ book, a spokesperson for Bill tells PEOPLE in a statement that by “relying almost exclusively on second- and third-hand hearsay and anonymous sources, the book includes highly sensationalized allegations and outright falsehoods that ignore the actual documented facts Mr. Gates’ office provided to the author on numerous occasions.”

In his own statement, Bill says, “I am grateful for Melinda’s critical contributions to the Foundation from its very beginning. As a co-founder and co-chair, Melinda was instrumental in shaping our strategies and initiatives, significantly impacting global health and gender equality.”

A rep for Melinda did not respond to a request for comment.

Bill and Melinda, who share three children, were married for 27 years before they announced the end of their relationship in May 2021 — but in a new interview with TIME published in June, Melinda said the pair had already been living separately and trading off who lived at the family home since the beginning of the COVID-19 pandemic in early 2020.

Opening up about their divorce for the first time in 2022, Melinda told CBS Mornings‘ Gayle King that there “wasn’t one moment” that led to their split but that “there just came a point in time where there was enough there that I realized it just wasn’t healthy, and I couldn’t trust what we had.”

While Melinda has never shied away from admitting that the divorce was painful, when speaking with TIME this year, she reflected on plenty of things to be excited about — including her “wonderful” life, which includes her work with Pivotal Ventures, an investment and charitable firm she founded in 2015, as well as her $1 billion pledge to help support women’s rights.

Melinda Gates arrives for a meeting at the Elysee Palace, amid the New Global Financial Pact Summit in Paris on June 23, 2023 in Paris, France.

Melinda French Gates.Christian Liewig/Corbis/Getty

“What I am doing now in full force is making sure that women’s rights are not only on the agenda, but that women are setting the agenda,” Melinda said during an appearance on The Late Show with Stephen Colbert in July.

She went on to say that since leaving the foundation she once shared with Bill, she could “use my full voice in any way I want to. And my full resources in any way I want to.”

“It’s something I’ve been saying about women in society; that they should have their full voice, their full resources, their full decision making authority,” she added. “Now I’m role modeling that.”

Billionaire, Nerd, Savior, King: Bill Gates and His Quest to Shape Our World is out now.