Joss Whedon's wife says their painful relationship left her with PTSD.

The Avengers director Joss Whedon’s image as one of Hollywood’s most feminist men has taken a hard knock after his ex-wife revealed he had multiple affairs throughout their 16-year marriage.

In a brutally honest post for The Wrap, Kai Cole exposes her former husband as a serial-cheater, saying the breakdown of their marriage and the sudden realisation of his lies left her diagnosed with a complex post-traumatic stress disorder.

“My entire reality changed overnight, and I went from being a strong, confident woman, to a confused, frightened mess,” she writes in the piece.

Whedon is best known as the creator of ’90s phenomenons Buffy The Vampire Slayer and Angel and, more recently, as the writer and director of Marvel’s blockbuster The Avengers and writer of its 2015 sequel, Avengers: Age of Ultron.

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He also has a reputation as one of the ‘nice guys’ of Hollywood – heralded as a feminist fighting for women’s rights and making sure they are portrayed as complex, multi-faceted humans in his movies. His cachet is so much so, that he’s been asked to speak at feminist events such as the Make Equality Reality Gala and has even accepted an award for his “for his courageous support of women’s rights”.

Cole makes the claim, however, that Whedon is a hypocrite.

“…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 scrutinise his writing as anything other than feminist,” she writes.

“Despite understanding, on some level, that what he was doing was wrong, he never conceded the hypocrisy of being out in the world preaching feminist ideals, while at the same time, taking away my right to make choices for my life and my body based on the truth.

“I want the people who worship him to know he is human, and the organisations giving him awards for his feminist work, to think twice in the future about honouring a man who does not practice what he preaches.”

Cole, who describes herself as a “very private person” says she only wrote her personal essay to set the record straight.

"I feel compelled to go on the record and clear up some misperceptions. I don’t think it is fair to me or other women to remain silent any longer."

Cole says that her husband first cheated on her on the set of Buffy and went on to have multiple affairs, the entire time maintaining the facade of a doting husband, presenting himself as "one of the good guys".

"There were times in our relationship that I was uncomfortable with the attention Joss paid other women. 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," she writes.

"He said he admired and respected females, he didn’t lust after them. I believed him and trusted him."

The LA-based architect, who separated from Whedon years ago, but just recently finalised their divorce, says she only found out about the affairs when he confessed them to her, in part in letter-form, as their marriage was "falling apart".

She says as he walked out of their marriage he justified his behaviour, telling her: "In many ways, I was the height of normal, in this culture. We’re taught to be providers and companions and at the same time, to conquer and acquire — specifically sexually — and I was pulling off both."

As Cole puts it, "He wanted it all; he didn’t want to choose, so he accepted the duality as a part of his life".

She says when he told her the truth she became a "mess" and was eventually diagnosed with complex PTSD, but for the past five years has worked hard to "make sense of everything that happened and find my balance again."

In response, a spokesperson for Whedon tells The Wrap his ex-wife's account "includes inaccuracies and misrepresentations which can be harmful to their family", but he would not comment "out of concern for his children and out of respect for his ex-wife".

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