Robert F. Kennedy Jr’s estranged wife, Mary, had at least three anti-depressants in her blood stream when she committed suicide in May, a Westchester County Medical Examiner’s autopsy report has revealed.

The autopsy report also showed that the recovering alcoholic had no booze in her system when she hung herself with a rope in a barn on her Bedford estate on May 16, according to the report, obtained by The Post.

The medical examiner found the 52-year-old pumped full of trazodone, desmethylvenlaxafine and venlafaxine — all classified as anti-depressants.

She died from asphyxia due to hanging, a finding supported by the injuries to her neck, the report stated.

Among the report’s more gruesome details was that Mary was brought to the medical examiner’s office still with “a beige rope around the neck” and “the knot present on this rope lying on her back with 9 loops,” the report said.

She had no food in her stomach.

At the time of her death, Mary and her ex, Bobby, an environmental advocate and son of former Sen. Robert F. Kennedy, had been embroiled in a bitter divorce and custody battle over their four children.

The couple’s legal woes became public in 2010, when police responded twice to the couple’s home following alleged domestic squabbles, Bobby filed for divorce, and she was charged with driving drunk.