Nancy Motes’ death was officially declared a suicide (as opposed to an accidental overdose) on Wednesday, Los Angeles coroner's officials confirmed, citing autopsy and toxicology tests performed on the deceased half-sister of Pretty Woman star Julia Roberts.

The 37-year-old Motes drowned in her bathtub after ingesting unnamed substances, officials said.

A comprehensive autopsy report due out later this month will include an inventory of the actual drugs that felled the troubled woman, who had an acrimonious relationship with her A-list sister throughout much of her life.

Roberts called Motes’ death “just heartbreak,” calling it one of the “tragic, painful, inexplicable things in the world.”

Motes fiancé John Dilbeck told the NY Daily News Wednesday that the latest reports serve “proof that Julia was manipulating the truth in terms of what happened,” claiming the Oscar-winner “persisted that this was just a drug overdose and that Nancy was a drug addict.

“I want everyone to know Nancy was not a drug addict,” he said. “This verdict from the coroner is more proof of that. I’m still suffering and in mourning, and this is one of the worst nightmares anyone can imagine.”