The shocking secret behind the MARY KENNEDY suicide shocker that tore two families apart!

ROBERT F. KENNEDY JR.’s estranged wife MARY did not want the KENNEDY clan to write off her suicide as an accident, so the tortured soul hanged her­self instead of overdosing on pills.

That’s the shocking secret behind the tragic death of the 52-year-old mother of four, whose lifeless body was found in a barn behind the fam­ily mansion in exclusive Bedford, N.Y., on May 16.

“Mary was deeply depressed, and felt she had no choice but to end her life,” a close friend told The ENQUIRER.

“She’d threatened to kill herself before with pills, but she believed that if she did, the Kennedys would pull out all the stops to cover up the tragedy. Instead, she decided to hang herself.

“In the end, she wanted to send a message loud and clear that her life had been destroyed by a Kennedy.”

Mary, an architect, gave up her career to raise a family and turn their home into an environmental showcase. But she battled problems with booze, and starting in 2007 cops were called to the mansion on a string of alcohol-related incidents.

Kennedy, 58, moved out in May 2010 and filed for divorce after 16 years of marriage. After that, Mary descended into alcohol and pre­scription drug use that included two DUI busts.

Kennedy, the son of slain Sen. Robert F. Kennedy and the nephew of assassinated President John F. Kennedy, gained temporary custody of the couple’s children, ages 10 to 17, in February. He’s been linked to “Suburgatory” actress Cheryl Hines since late 2010.

“Mary was in debt and losing her children, and her husband, whom she still loved, was in a relationship with a Hollywood star,” the source added. “It all made her feel as if she had nothing to live for.”

Robert DuPont, a longtime friend of Mary, told The ENQUIRER: “Mary had known the Kennedys since she became friends with her husband’s younger sister Kerry at boarding school.

“Kerry was always trying to fix her up with one of the Kennedy boys, and Mary was Kerry’s maid of honor at her wedding in 1990. When she married Bobby, Mary thought her life was complete.

“I saw Mary recently at an art show in New York. She was very sweet but appeared to have been drinking. When I asked how she was doing, she said, ‘As best I can, under the circum­stances.’

“Mary never got over the fact that Bobby had filed for divorce, and she couldn’t accept that he was dating Cheryl Hines.

“Ever since she was a young girl, all Mary ever wanted was to be a Kennedy. By taking that away, it was as if she didn’t exist anymore.”