Mimi O’Donnell might have known her partner of nearly 15 years, Philip Seymour Hoffman, was headed down a path of destruction. The costume designer split with the Oscar-winning actor just months before his untimely passing, the Daily Mail reported on Monday. The “Capote” actor was found dead in his New York apartment on Sunday morning after he reportedly overdosed on Saturday night.

The 46-year-old Hoffman was found alone in his West Village apartment the morning of Super Bowl Sunday, just blocks away from the home he shared with O’Donnell and their three children. Apparently his estranged partner told New York police she suspected Hoffman was high the last time she saw him alive.

The actor was reportedly supposed to meet O’Donnell and their children at a park. When he failed to show up, the Daily Mail said she asked for his assistant Isabella Wing-Davey to check on him. She also told the NYPD he sounded high when she talked to him on the phone Saturday night.

Now the NYPD has launched an investigation to find the dealer who sold Hoffman the drugs. “An internal email went out to all supervisors asking if anyone has had any experience with those brand names of drugs,” a law enforcement source told The New York Post. “They’re going to try to find the source.”

Showbiz Spy wrote Hoffman’s estranged partner was heartbroken when she found out about her children’s father’s tragic death. A source told the site: “Mimi is inconsolable.” The insider added though Hoffman struggled with substance abuse, he was trying to get better after his May 2013 relapse. Though O’Donnell is struggling with his death, the insider said she will be tough for their children. “She will have to stay strong for the sake of their kids.”

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