First he was a teen pop idol. Then he was Canada's best known trainwreck. Now, he's made a comeback. Justin Bieber has had quite the rollercoaster ride when it comes to fame. The 21-year-old rarely opens up in interviews, but recently, he let his guard down for his cover interview with Billboard magazine. Here are the highlights.

Related: How Justin Bieber made a comeback

1. He's starting a new chapter. Bieber has been doing a lot of apologizing the past few months. His latest single is even called "Sorry." In his Billboard interview, he takes the reporter to his church and tells him he wants the focus to be on something other than himself. Is this really the end of public urination and Brazilian brother Bieber? Time will tell.

2. Being a child star was hard. When "Baby, Baby" came out in 2010, the world became Bieber's oyster and he became mega famous mega fast. But Bieber tells Billboard it was hard for him to deal with. "I wouldn't suggest being a child star," he says. "It's the toughest thing in the world."

3. He still misses Selena Gomez. Bieber and his ex Selena Gomez have had a rocky relationship for years, and Bieber says it's still too soon for him to move on and start dating someone new. "When you love someone that much, even if something comes between you, it's a love that never really dies."

Click here for the full interview.

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