Steven Avery’s former fiancée, Lynn Hartman, is opening up about the letters she received from the Making a Murderer star while in prison — and the bizarre instructions he used to give her to destroy the “evidence.”

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“He’s very manipulative,” Hartman tells In Touch of the man who is depicted as mild-mannered on the Netflix original series. “I’m afraid for my life.”

Hartman and Avery began dating in 2016 and dated for eight months before breaking up in the fall. He reached out to her after she made an appearance on Dr. Phil in October, during which he felt she portrayed him in a “bad light” after admitting she wouldn’t live alone in the woods with him. That’s when the threatening letters arrived — prompting her to reach out to the correctional facility where he’s serving a life sentence for the 2005 murder of Teresa Halbach and had them issue a no-contact order.

“I feel threatened by him, and I’ve also gotten threats from his followers,” Hartman tells In Touch, exclusively.

In one of the letters she shared with In Touch, he demands that she “destroy this letter by fire”; in another, he threatens her directly, saying, “I don’t wont [sic] to hurt you or the kids! So you have to promise me you will help us forever.”

His preoccupation with fire is especially concerning considering cops say he burned his 25-year-old victim’s body after brutally killing her.

“Given his history and experience with fire, this is certainly a warning sign or red flag,” New York-base psychologist Jean Cirillo — who has never treated Avery — tells In Touch. “He gets a lot of press for being a victim, but anybody who writes like this to a woman he has affection for has a dark side.”

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Hartman tells In Touch she regrets ever entering a relationship with Avery.

“I kick myself because I believed he was innocent,” she says. “I truly loved him [and] was in denial. But I now believe Steven’s guilty of killing that girl.”

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