Glee's Cory Monteith Reveals "Out of Control" Drug Habit, Rehab Stay

Life wasn't always a soaring musical number for Glee's Cory Monteith.

Now 29, the Victoria, British Columbia native was a child of divorce who began cutting school to get drunk and smoke pot at the age of 13. He finally dropped out of school at the age of 16, and hit the drugs harder than ever, he tells Parade.

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"I burned a lot of bridges," he says. As for his drug use, he says he did "anything and everything, as much as possible...I had a serious problem."

Finally, his mom and family friends, fearing he "could die," staged an intervention for Monteith, then 19.

"That's when I first went to rehab," he reveals. But the first stay didn't stick. "I did the stint but then went back to doing exactly what I left off doing."

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Monteith said he reached rock bottom -- and a turning point -- when he "stole a significant amount of money from a family member," he explains. "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."

The future star was given an ultimatum: Get clean and sober or be turned over to the police.

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"I was done fighting myself," he admits. "I finally said, 'I'm gonna start looking at my life and figure out why I'm doing this.'"

After moving in with a pal in a nearby town, kicking his habit and landing a job as a roofer, Monteith began rebuilding his life -- and soon started working with an acting coach.

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"I don't want kids to think it's okay to drop out of school and get high, and they'll be famous actors, too," cautions Monteith, who finally received his high school diploma from an alternative school in Victoria this past spring. "But for those people who might give up: Get real about what you want and go after it. If I can, anyone can."