Martha Stewart threatened to burn down her own home over husband's cheating 'right on our property'

For a long time, Martha Stewart kept the lid on the more unruly details of her personal life sealed tight. With her new Netflix documentary, Martha, she's beginning to let off a bit of the pressure.

The lifestyle impresario details the painful saga that led up to her 1987 separation and 1990 divorce from her husband Andy Stewart in Martha. Stewart recounts discovering that Andy had struck up an affair with a woman named Robin, who lived on their Connecticut property. Stewart remembers "[kicking] her out immediately, like 'What the hell are you doing?'" after she found out. "Andy betrayed me right on our property. Not nice."

Though Stewart pointedly declines to go deep on her emotions over past hardships in the new interview conducted for Martha, she shares letters that chronicle with searing intensity the dissolution of the relationship. "Again, I feel betrayed and all alone," one begins. "When you tell me that this is no longer your home, after all we did here together, why shouldn't I say I'm going to burn it down? I am to go to San Francisco to talk about weddings and my wonderful life. I hope you're enjoying your freedom, and I hope my plane crashes."

Recalling the experience in fuller detail, Stewart explains that "Robin worked for me, and she had lost her apartment or something, and I said, 'You can move into the barn on the lower two acres.' We had a little apartment down there. When I was traveling, Andy started up with her. It was like I put out a snack for Andy."

By that time, the Stewarts had been living in their iconic Turkey Hill Road house in Westport, CT, for over a decade. Martha had previously worked in New York as a model and a stockbroker but found her true calling by opening a catering business in the mid-1970s. She was soon catering White House galas and corporate soirees, which led to several book deals, the Martha Stewart Living magazine, a TV series, and a billion-dollar media empire.

Though Stewart acknowledges that there was less and less personal time for her and Andy, the publisher at Harry N. Abrams, Inc., she maintains that "he's the one who wanted the divorce, not I."

Stewart continues, "He was throwing me away. I was 40 years old; I was gorgeous. I was a desirous woman, but he was treating me like a castaway. He treated me really badly, and in turn, I guess I treated him badly. I always said I was a swan, and like all swans, I was monogamous. And I thought monogamy was admirable; I did. But it turns out it didn't save a marriage." That's about as emotional as Stewart lets herself get in Martha and, on a dime, fixes her stare onto the camera to request, "Can we get onto a happier subject?"

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With the once-in-a-generation knack for practical tutelage that paved the way for her unprecedented success, Stewart proceeds to command, "Young women listen to my advice. If you're married and your husband starts to cheat on you — he's the piece of s-, and look at him as a piece of s- and get out of it. Get out of that marriage."

Stewart did eventually get out of her marriage to husband Andy, and began dating the billionaire software architect Charles Simonyi. Stewart and Simonyi remained linked for many years, but Stewart recounts that her 2005 conviction for obstruction of justice, following a federal investigation into allegations of insider trading, caused him to stray as well.