The results of the Cory Monteith's autopsy revealed that the 31-year-old died of a heroin and alcohol overdose. In a statement revealed by the British Columbia Coroners Service in Vancouver, the actor died from a "mixed drug toxicity, involving heroin and alcohol."

Meanwhile, it has been revealed that the late actor had been gushing about his plans to move in with his girlfriend and GLEE co-star Lea Michele, just hours before his sudden death on Saturday.

A source close to the late star revealed to RadarOnline that he had talked about moving in with Michele. "We talked about him moving in with Lea and that was really it," the source said. "He adores her."

Friends who were photographed hanging out with the GLEE star just hours before his death said that he was not drinking when they were with him. "He wasn't drinking when we were with him. He seemed really happy and healthy when I saw him."

The autopsy had been fast-tracked due to intense public interest after the 31-year-old star was found dead in his hotel room in Vancouver on July 13.

Michele is said to be "inconsolable" at the loss of her boyfriend, whom she has been dating for about two years.

The actress revealed a statement Tuesday after the results of the autopsy were revealed. In a statement to PEOPLE, Michele's representative said: "Lea is deeply grateful for all the love and support she's received from family, friends, and fans. Since Cory's passing, Lea has been grieving alongside his family and making appropriate arrangements with them. They are supporting each other as they endure this profound loss together. We continue to ask the media to respect the privacy of Lea and Cory's family."

Michele and Monteith had been scheduled to film the fifth season of Glee in mid-August. Now producers must figure out how to explain the loss of Monteith's character on the show, with Michele having to act it out.

The pair was reportedly very happy together and had been inseparable. They had been pictured together on numerous events, and Michele had supported Monteith when he went into rehab for substance addiction in April. She told People magazine: "I love and support Cory and will stand by him through this. I am grateful and proud he made this decision."

Michele had told Marie Claire magazine earlier this year: "I don't even remember a time when he wasn't my boyfriend. No one knows me better than Cory. No one knows what it's been like to go through this more than he does," she told Marie Claire magazine. "Feeling like you have that net underneath you allows you to jump higher and go farther…He makes me feel like I can do anything. For the first time in my life, I feel really, really settled and happy. I feel like the luckiest girl in the world."

Foul play has been ruled out in Monteith's death. An initial police report stated: "There is no evidence to suggest Mr. Monteith's death was anything other than a most-tragic accident. Mr. Monteith's family has been made aware of the circumstances surrounding the death. On behalf of family members, the BC Coroners Service asks that the media respect their privacy at this difficult time."