Justin Bieber ‘Shut Himself Off From the World’ After Diddy’s Arrest: ‘People Are Genuinely Worried’

Justin Bieber is on the verge of a total collapse as he faces the shattering possibility that sordid details about his relationship with Sean "Diddy" Combs will soon be exposed for all the world to see, sources exclusively tell In Touch.

Insiders close to the 30-year-old "Stay" singer say he's "shut himself off from the world" as he wrestles with his disturbing past, when he was a fresh-faced 15-year-old trying to impress a music industry mogul whose alleged degenerate ways are only now coming to light.

"No one knows what's going on with Justin," says a member of his inner circle. "It's like he's fallen off the map since Diddy's arrest and all the sick details coming out. People are genuinely worried about him."

Sources say Justin — who recently became a dad for the first time with model wife Hailey Bieber — partied hard during Diddy's now-infamous "Freak Off" orgies.

"Dealing with that and being a new dad probably has him stressed as hell," says the insider.

Justin was just 13 in 2008 when he was signed to manager Scooter Braun and Usher's music label. Through Usher, he met Diddy, now 54, and became the rap impresario’s protégé.

As a recently unearthed video reveals, the two buddies spent a wild weekend together in 2009. In the video, the rapper alarmingly says, "Where we're hanging out and what we're doing, we can't really disclose, but it's definitely a 15-year-old's dream. I have been given custody of him. I don't have legal guardianship of him, but for the next 48 hours, he's with me, and we're gonna go full crazy."

It's long been rumored Diddy plied Justin with drugs and booze and brought him to clubs when he was underage. Justin himself has confessed he struggled with drug use as a young adult while he dealt with pain that nearly drove him to do the unthinkable.

"I think there were times when I was really, really suicidal, like man is this pain ever going to go away," he once shared.

Sources say Justin, who has seen his star cool considerably in recent years, is terrified details of those troubled times will be laid bare as Diddy faces sex trafficking and assault charges in what promises to be a sensational criminal trial.

Recent images of a gaunt Justin have raised new fears about his state of mind.

"I can only imagine the horrors he carries around with him," confides the insider. "And now he has to deal with all this stuff being dredged up, threatening his marriage and career. No one would be surprised if he has a complete breakdown!"