Martha Stewart Details Enduring Years of Infidelity by Her Husband Including One Affair 'Right on Our Property'

Martha Stewart has been teaching for decades — through cookbooks, on TV, in magazines that bear her name. Now she’s schooling the world on the events of her own storied life in the new Netflix documentary Martha.

“I just hope that everyone gets a few life lessons from the film and understands what’s been going on,” Stewart tells PEOPLE.

No hard topic is off the table. Stewart, 83, reveals that both she and her ex-husband, publisher Andy Stewart, had affairs during their marriage. The couple were married from 1961 to 1990 and share daughter Alexis, born in 1965.

Early in the film, Martha recalls kissing a “very handsome guy” in Florence’s Duomo on her European honeymoon while Andy was at their hotel.

“He didn’t know I was married,” she says of the stranger. “I was this waif of a girl hanging out in the cathedral on Easter Eve. He was emotional. I was emotional. It’s just because it was an emotional place. It was unlike anything I’d ever experienced.”

Martha goes on to share that she once had a “very brief affair” with a “very attractive Irish man” while she was working as a stockbroker in the late ’60s.

“It was nothing,” she says. “I would never have broken up a marriage for it."

Andy told producers he “didn’t stray” until she had. 

“He was not satisfied at home,” Martha says in the film. "I don’t know how many different girlfriends he had during this time, but I think there were quite a few.”

“Young women, listen to my advice, if you’re married and your husband starts to cheat on you, he’s a piece of s---,” she adds in a clip previously seen in the doc’s trailer. “Get out of that marriage.”

Later in the film, Martha’s friend Kathy Tatlock recalls rumors that Andy had “some sort of involvement with the girl who was doing the flower arrangements” at Turkey Hill Farm (the couple’s Westport, Conn. home).

Martha says her employee needed a place to stay, so she invited her to move into an apartment in a barn on their property.

“When I was traveling, Andy started up with her,” she says. “It was like I put out a snack for Andy.”

Martha says she confronted them about the affair. “I kicked her out immediately,” she says. “You know, 'What the hell are you doing?'”

“Andy betrayed me, right on our property,” she continues. “Not nice.”

When Martha wasn’t up for speaking on camera, she provided filmmaker R.J. Cutler with personal letters that revealed her inner thoughts. “I am agonizingly jealous of your other women," she wrote to Andy during this period.

They divorced after 29 years.

“He’s the one who wanted the divorce, not I," says Martha. "He was throwing me away. I was 40 years old. I was gorgeous. You know, I was a desirous woman. But he was treating me like a castaway. He treated me really badly. And in return, I guess I treated him badly.”

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Martha and Andy renovated Turkey Hill — their “dream home”— which spawned Martha's career. The house is long sold, and "I haven't talked to him for over 20 years, sadly,” she says.

At the New York premiere of Martha on Oct. 21, she told PEOPLE she has "no idea" if he's seen the film.

Martha is now streaming on Netflix.