New details are coming out regarding the evening before Cory Monteith's death.

His acting coach and friend Andrew McIlroy is speaking out, stating that the Glee star, 31, was hanging out with three pals, who were "positive influences," on July 12, the evening before his death.

"They weren't strangers, they weren't bad guys. They were longtime sober friends. Cory knew them maybe 10 years. Essentially, he had spent time with [them] as sober people," McIlroy told PEOPLE. "They were not using with him [that night]. There was no double life up here."

"He was just recently out of rehab and he was good," he said. "He was happy to be breathing fresh air and putting in full days and being active."

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Monteith was found dead in his Vancouver hotel room due to a lethal dose of heroin and alcohol on July 13.

He had checked into the hotel on July 6 and had been expected to check out on the 13th. When he had not done so, hotel staff checked his room and found him deceased.

the BC Coroners Service confirmed Monteith died from a mixed drug toxicity, involving heroin and alcohol. The post-mortem testing, which included an autopsy and toxicological analysis, seem to confirm this was an accident.