Joss Whedon's feminism is something of a complicated matter.

By some, he's been posited as a kind of ultimate feminist ally. He created Buffy the Vampire Slayer, after all, and has always been vocal about Hollywood's need to improve its onscreen representation of women.

Others, however, have been more sceptical about his treatment of female characters, particularly Black Widow's storyline in Avengers: Age of Ultron and the leaked Wonder Woman script for his version of the project from back in 2005.

Whedon's ex-wife Kai Cole, an architect and producer, has now penned a painful personal essay for The Wrap, in which she accuses the writer/director of engaging in a string of affairs over the course of their 16-year marriage while attempting to use his feminist credentials as a way to shield himself from criticism.

The pair met in 1991, marrying four years later, with their relationship developing into a deeply collaborative one: Cole was the one who convinced him to turn Buffy the Vampire Slayer into a TV show after its disappointing film outing.

"There were times in our relationship that I was uncomfortable with the attention Joss paid other women," Cole writes. "He always had a lot of female friends, but he told me it was because his mother raised him as a feminist, so he just liked women better. He said he admired and respected females, he didn’t lust after them. I believed him and trusted him."

However, she claims Whedon had his first affair on the set of Buffy, attempting to justify his actions many years later by telling her: "I was surrounded by beautiful, needy, aggressive young women. It felt like I had a disease, like something from a Greek myth. Suddenly I am a powerful producer and the world is laid out at my feet and I can’t touch it."

It was only after their marriage had dissolved that the director admitted to the extent he'd been living "two lives", with Cole alleging multiple affairs over the years.

"But I now see how he used his relationship with me as a shield, both during and after our marriage, so no one would question his relationships with other women or scrutinize his writing as anything other than feminist," she continues. "Now that it is finally public, I want to let women know that he is not who he pretends to be."