Even as A.J. McLean found riches and worldwide fame with the Backstreet Boys, the 23-year-old wrestled with "internal demons" and struggled to find himself, according to his bandmates.

His image as a tattooed bad boy hid deep-seated despair, and he drank heavily to try to escape his problems, his bandmates said, leading to the rehab stay that will interrupt the Backstreet Boys' touring schedule for a month (see [article id="1445019"]"Backstreet Boys Postpone Tour As A.J. McLean Seeks Treatment"[/article]).

The rest of Backstreet said some of A.J.'s problems stemmed from growing up without his father.

McLean's grandmother, who recently died, served as a second mother for the singer, Kevin Richardson told MTV News. As a young child, McLean lived with his grandparents and his mother, who divorced his father when he was 4.

"I think when [A.J.'s grandmother] passed away, that just sent it over the edge," Richardson said. "But ... he has internal demons he has to deal with that happened before this. He never had a father figure in his life."

McLean told MTV News last year that when his father showed up after years of separation, it was difficult to accept him.

"My father was never really talked about a lot growing up," he said. "[When he returned], it was kind of awkward, but he kind of expected me to jump back into it and just become [his] son all over again. I couldn't do that."

Bandmate Howie Dorough said A.J. "was consistently trying to figure himself out. I mean, fame brings a lot of stuff to people. ... The money and all that stuff doesn't always bring you happiness.

"I think A.J. through all this was looking for support and trying to find himself," Dorough said. "As we all know, A.J's the crazy rebel with the tattoos, always trying to find that security."

Lou Pearlman, who helped bring the Backstreet Boys together and was later fired as their manager, blamed McLean's problem on years of living in the high-stakes pop world.

"A.J. was the first Backstreet Boy and has been under the pressures of extreme success and the rigors of touring for a long time," Pearlman said in a statement. "It is understandable that something like this could happen. Everyone should be supportive of A.J. during this difficult time."

The Backstreet Boys sued Pearlman — who also brought together 'NSYNC — in 1998, saying an unfair contract with him had rendered them "indentured servants." The case ended in an out-of-court settlement.

McLean told Rolling Stone last year that he struggled with depression and a drinking problem in the early days of the Backstreet Boys. But his behavior became so extreme that his bandmates felt it was damaging the group.

In June, they confronted McLean during rehearsals in Orlando, Florida, for their summer tour opener, according to Richardson.

"We had a big powwow and we were like, bro, we don't like what we're seeing out of you, we think you have a problem, you need some help," Richardson said.

But it was ultimately McLean's decision to enter rehab, his bandmates said. McLean had a tearful meeting with them on Sunday, before leaving for an unspecified rehabilitation center, according to Dorough.

"He cried to us. He said he was scared about all this but that he knew it was the right thing to do and he didn't want to let us down, but this is something he had to do with his life in order to be stronger and come back, for us to be a tight unit."

Although Dorough raised the possibility of BSB continuing their tour without McLean if he needs more time in rehab, the group's former musical director and drummer said it would be hard to imagine the Backstreet Boys without A.J.

"I think he's an amazing talent — he's unbelievable. He has more soul than he knows what to do with," said Tim Berkebile, who worked with the Boys from 1996 to 2000. "He's completely essential to their sound — he delivers that soulful approach, that digging down deep."

For MTV News' full-length interview with the group, check out [article id="1445050"]"Backstreet Boys: 'We Want To Be Honest.' "[/article]

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