"Glee" star Cory Monteith was a high school drug fiend before

Cory Monteith may play a sweet high school student on FOX’s musical hit “Glee,” but the young actor has a dark past.

“I’m not Finn Hudson,” declares Monteith in an interview with Parade Magazine. “I’m lucky on so many counts—I’m lucky to be alive.”

By the age of 13, the once-promising student was ditching school to get drunk and high.

Monteith was bounced from twelve different schools by the time he turned sixteen, including ones troubled teens. “I burned a lot of bridges,” he says. “I was out of control.”

Sweet sixteen was blurred by a haze of various drugs for Monteith, “Anything and everything, as much as possible,” he says. “I had a serious problem.”

But the time he turned 19, his family and friends desperately staged an intervention. “That’s when I first went to rehab.”

To the dismay of his loved ones, rehab didn’t work: “I did the stint but then went back to doing exactly what I left off doing.”

Fortunately, Monteith experienced a “crystallizing event” that was his rock bottom.

“I stole a significant amount of money from a family member,” he says. “I knew I was going to get caught, but I was so desperate I didn’t care. It was a cry for help. I was confronted and I said, ‘Yeah, it was me.’ It was the first honorable, truthful thing that had come out of my mouth in years.”

Monteith’s family gave him one last chance: Get clean, or the family member would report him to the police and press charges.

“I was done fighting myself,” says Monteith. “I finally said, ‘I’m gonna start looking at my life and figure out why I’m doing this.’”

The actor moved in with a family friend and got a job as a roofer. Monteith quit using drugs and started working with an acting coach. The experience was the first time Monteith felt like he was “working hard and being good at something.”

The actor is speaking out now because he doesn’t want teens to think that “it’s okay to drop out of school and get high, and (think) they’ll be famous actors, too.”

And Monteith has some advice for other addicts who are struggling with their lives and careers. “Get real about what you want and go after it,” he says. “If I can, anyone can.”