RFK, Jr.’s estranged wife MARY RICHARDSON KENNEDY might have suddenly changed her mind after slipping a noose around her neck to commit suicide, according to the coroner’s grim autopsy report.

The report sheds new details on Mary’s tragic May 16 death — when her body was found by a worker in a barn at her Bedford, New York home — saying that physical evidence indicates a possible last-minute attempt in vain to break free of her own strangulation.

Westchester County Medical Examiner Dr.Kunjlata Ashar said in the had bruised fingers and blue fingernails, indicating a possible struggle to stop the fatal process.

The doctor told the NY Daily News: "The fingers from both of (Mary's) hands were between the rope and the neck. The fingernails were cyanotic [blue] because of compression of the fingers, as they were between the rope and the neck.

It's also possible, Dr. Ashar wrote, "the fingers caught in the noose may suggest that she was trying to place the rope around her neck."

Mary’s toxicology report, the doctor said, indicated no alcohol in her system but there were traces of anti-depressive meds in her system. Often, such drugs cause contradictory effects causing the opposite reeactions in patients with long term disorders.

 Mary's issues with drugs and alcohol became a matter of public record following two arrests: for driving while intoxicated in May 2010, three days after Robert filed for divorce; and later that year for driving under the influence of drugs, although the charge would be later dismissed.

As THE ENQUIRER reported previously, Mary was upset that Robert was involved with actress Cheryl Hines – seemingly flaunting their relationship in the media much to the despair of the career Kennedy wife.

Mary had married Robert, the son of slain New York Senator and former Attorney General Robert Kennedy in 1994 on a boat coasting in the Hudson River Valley. His uncles were JFK and Ted Kennedy, reported.