Mary Richardson Kennedy pummeled Robert F. Kennedy Jr., threatened suicide in front of their children and ran over the family dog, according to a leaked divorce document whose details were revealed in published reports Sunday.

The sealed, 60-page affidavit by Robert F. Kennedy Jr. -- disclosed by Newsweek and its sister publication, The Daily Beast -- paints vivid details of the tumultuous domestic life of the couple in the months before his wife's suicide at her Bedford home May 16.

The affidavit, filed last September in State Supreme Court in White Plains, outlines Mary Richardson Kennedy's drinking problem, mood swings and erratic behavior as the couple grappled with a bitter divorce fight.

One instance detailed in the papers came on May 26, 2011, when Mary Richardson Kennedy ran over and killed the family's dog, Porcia. Afterward, she asked her estranged husband to come over and spend the night to calm the children. She said she intended to kill herself unless he agreed to end divorce proceedings and reunite.

When Robert Kennedy Jr. arrived, Mary Richardson Kennedy was drunk and started punching and screaming at him as their son Aidan looked on, according to the court documents.

In addition to Aidan, 10, the Kennedys had three children: Conor, 17; Kyra, 16; and Fin, 14.

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The affidavit said Mary Richardson Kennedy hit her husband about 30 times, calling him a demon, a fraud, a philanderer, an adulterer and a sex addict.

Robert Kennedy Jr. contends in the papers that the physical abuse started even before the couple married in 1994.

He said he had considered divorce as early as three years into their marriage but had not begun proceedings until May 2010. However, he admitted in the court papers to having affairs starting in 2003.

Running throughout the narrative is Mary Richardson Kennedy's ongoing battle to remain sober. She was charged with driving under the influence twice since the divorce proceedings began and was quoted by her housekeeper as wondering aloud, "Why, why, why [do] I drink?"

The Newsweek story, written by a Kennedy biographer, Laurence Leamer, also reported that Mary Richardson Kennedy's psychotherapist diagnosed her condition as a "borderline personality disorder" that can exhibit unwarranted anger, recklessness, feelings of emptiness and lack of identity, and threats of suicide.

In the court filings, Robert Kennedy Jr. contended that his wife was abusive to his children from a previous marriage.

In one incident, he found items belonging to one of the children hidden underneath her clothing, according to the court papers. About five years later, he said, his daughter told him that Mary Richardson Kennedy would take her into a closed room and berate her for a laundry list of faults.

The Newsweek story also reported that in the weeks leading up to her suicide, Mary Richardson Kennedy asked her housekeeper's husband to buy a rope she said she needed to make a sofa, and she searched the Internet for instructions on how to make a noose. The housekeeper, her husband and Robert Kennedy Jr. later would find Mary Richardson Kennedy, 52, hanging from a rope in the barn on the Bedford estate.

After the body was found, several of her siblings went to the house while Robert Kennedy Jr. was away and searched through drawers, apparently to look for a suicide note.

When he returned, her siblings asked him to leave. "You have killed my sister," Nan Richardson said to him, according to witnesses in the Newsweek account.

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Calls to Mary Richardson Kennedy's brother, Tom Richardson, and her divorce lawyer, Patricia Hennessy, were not immediately returned.

Efforts to reach Robert F. Kennedy Jr., the vice chairman and chief prosecuting attorney at the Ossining-based environmental organization Riverkeeper, were unsuccessful.