The 32-year-old "Work Bitch" singer gave a behind-the-scenes glimpse at her personal life, as well as the four-month journey preparing for her upcoming two-year "Britney: Piece of Me" Vegas stint.

Britney Spears gave an inside look at her personal and public lives in the two-hour E! documentary I Am Britney Jean, timed to the 32-year-old singer's two-year Las Vegas show at Planet Hollywood that kicks off Dec. 27.

The doc chronicles the Spears' four-month journey in preparing for the upcoming Britney: Piece of Me gig, as well as the multitude of personal and professional obligations, like music video shoots, rehearsals and figuring out the flow of the show.

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The Hollywood Reporter compiled 12 interesting and revealing moments from I Am Britney Jean.

Spears prefers not to care about what people think anymore. It appears age has helped Spears see things a lot more clearly. "When I first started out, I didn't care what anybody thought of me. I was happy to be there. I was like, 'This is great!' But then 10 years later, I realize there's a lot of mean things on the Internet," she said. "But before the naivete in the whole thing was just brilliant because it was like you can't really control what they think so you can't really worry about what they think. That attitude is the one to have."

Spears felt "alienated from the public." Though she didn't pinpoint an exact time period, one could probably guess what she was referring to. In the doc, Spears said she felt "alienated from the public" when she couldn't go out without having 20 paparazzi following her. "But as time passed, they lightened up and they went away, after I wouldn't come out of the house for two years," Spears said. "It was a trying time. It was kind of confusing for me. Personally, I'm a shy person and I'm particularly not really made for this industry because I am so shy. It's not something I deal with so well."

Spears still struggles with speaking her mind. "I'm not saying it's good to be a bitch, but a lot of times in this industry it's better to speak up and say what's on your mind, which I have a problem with," she said.

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Spears on dealing with pressure. "Pressure is a funny thing. Sometimes I tend to go inward when I'm under pressure," she said. "I tend to keep it all in. I don't express myself too much. If I'm really nervous, I'm really quiet. But I think I thrive under pressure."

Spears shares her motto on love. "Love is just an unexplainable thing and there's a saying that I have in my bathroom in Louisiana. It says 'Go beyond reason to love, for it's the only safety there is.' And it's true you should always go beyond reason to love and to be with the person you want to be with and to be cherished and to be treasured. I think it's why we're here as people," she said.

Spears on believing in heaven. During a one-day shoot -- which should have been done over two days -- for the video content that will be used for the Britney: Piece of Me show, Spears said, "I definitely believe in heaven. I know there is a place beyond our wildest dreams."

The Vegas residency is a career retrospective. Sure Spears was a member of The Mickey Mouse Club, but it was "...Baby One More Time" in the late '90s that catapulted her into the mainstream. Her upcoming Vegas show, Britney: Piece of Me, is meant to serve as a 24-song, seven-act career-spanning retrospective covering the past 15 years. Spears says she wants her fans to get "a part of my soul" with the show "because I'm going to put my heart and soul into this."

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Why did Spears agree to a two-year Vegas stint? As Spears said in the doc, it was so there was a sense of stability for her two children. "I figured it'd be a really good place for the children and the family," she said. "It was kind of like an ideal situation."

Spears opens up about her boyfriend. The doc saw the entire Spears clan together for Thanksgiving and it was then the usually private singer talked briefly about her current love, David Lucado. "He's just a simple guy. He's funny. He's passionate. He's just a good guy. He gets what I do so it works out," Spears said.

Spears' takes a look back at her past concert wardrobe. The singer admitted that on her first tour in 1999, supporting ...Baby One More Time, she wore "ugly things" (i.e. oversized Tommy Hilfiger overalls and a white pleather suit with bright pink knee/elbow pads). After stepping it up for the 2000 Oops! I Did It Again Tour, Spears called the 2004 Onyx Hotel Tour her "sexy" one. "I wouldn't be that promiscuous these days," Spears said of the new show.

Spears toys with adding a last-minute track to show. For much of the doc, Spears was seen grappling with whether or not to put the new song "Alien" into the Vegas show, waiting until the last moment to decide not to do so. Instead, it will be included in the second set of Vegas shows "because it'll be out by that time and be a single," a decision longtime manager Larry Rudolph agreed with.

Spears calls "Piece of Me" her biography. The way she told it, the song off the 2007 album Blackout is popular because it detailed her journey in the music business and the often grueling life in front of and behind the cameras. "I'm relating to it with how I started at 17 years old and how the paparazzi is with me and what I go through when I go out sometimes and me being a mother," she said. But for Spears, her perspective on the song has changed as the years passed. "Now I look at it more like a superstar, like super-confident 'You want a piece of me?' "

Email: Philiana.Ng@THR.com

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