Story highlights Kristin Beck served as a Navy SEAL for more than 20 years

Then named Chris Beck, she deployed in Iraq, Afghanistan and Africa

Beck retired in 2011 and has since come out as transgender

"No one ever met the real me," she says

After years spent fighting in some of the world's worst wars, former U.S. Navy SEAL Kristin Beck says she knows what she wants.

"I want to have my life," she told CNN's "AC360."

"I fought for 20 years for life, liberty and the pursuit of happiness. I want some happiness."

Beck recently came out as transgender.

She wrote about the experience in a book, "Warrior Princess: A U.S. Navy SEAL's Journey to Coming out Transgender."

Trapped in a man's body

As a man named Christopher Beck, she deployed as a SEAL 13 times, including operations in Bosnia, Afghanistan, Iraq and elsewhere. Along the way, Beck earned a Bronze Star and a Purple Heart.

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Identifying herself as a woman, Beck has felt trapped in the wrong body since grade school, but didn't come out until after leaving the military in 2011.

Doing so earlier would have been too big a risk because in the United States, transgender men and women are banned from military service.

"That's a chance that -- if I took it -- I might be dead today," she told CNN's Anderson Cooper last year.

The CNN Film, "Lady Valor: The Kristin Beck Story," offers a fascinating glimpse of Beck's life. "I just wanted to tell someone my story," she says in the film. "And maybe set an example for some of the younger generation -- just say that I'm still a human being, and I deserve dignity and respect."

Beck says she deals with "a lot of prejudice out there. There's been a lot of transgender people who are killed for prejudice, for hatred. When the book came out -- some amazing support and some amazing praises -- but also some pretty amazing bigotry and hatred."

In the film, Beck talks candidly about how she reacts to prejudice. "I just try to be friendly, and I just say 'Hi, how are you doing?' You know, 'Good to meet you. I was that Navy SEAL, you know, transgender, you might've seen me on TV.' And they go, 'Oh, oh wow.' And then they realize that maybe trying to get into a fight with me wouldn't be a good idea. Maybe they should be nice."

Beck says she doesn't need people to love, or even like, her.

"But I don't want you to beat me up and kill me. You don't have to like me, I don't care. But please don't kill me."

'No one ever met the real me'

Beck explained her years of hiding as living like an onion.

Deep down, under various layers, or skins, she hid her female persona.

"It is a constant, but as you suppress and as you bottle it up, it's not like on that surface," she told Cooper.

"You would never notice it because I can push it so deep, but then it does kinda, like, it gnaws at you. So it's always there."

In the film, Beck pulls back the curtain on her unique childhood, when she used to pretend to be sick so she could stay home from school and indulge in her secret. "I would put nail polish on. I could have, you know, a pair of my sister's shoes on," Beck said. "It was like a reset, it was like a vacation for me. So I had my vacation away from Chris."

Beck believes she might have wanted to become a SEAL because they are "the toughest of the tough."

She thought: "I could totally make it go away if I could be at that top level. ... Maybe I could cure myself."

But the feeling of being born in the wrong body never went away.

And for her entire military career, Beck kept her secret.

She said virtually no one, out of the thousands of people she worked with, knew the truth -- it was so well hidden.

"No one ever met the real me," she said.

'True brotherhood'

Though her identity was hidden, the rest of what Beck offered was true.

"I gave true brotherhood. I did my best, 150% all the time, and I gave strength and honor and my full brotherhood to every military person I ever worked with."

Beck married a woman and had children. "I was just trying to fit in to the stereotype American dream, exactly what my parents and everyone expected of me," Beck says in the film. "I met someone who's -- who's awesome, you know, we got along good."

Beck chose to reveal the secret to her wife slowly, to "see what the acceptance level" was. "She wasn't totally digging it. So she had no idea what she was getting into. Definitely wasn't the top on her list of things that she wanted, so it hurt."

As much of mainstream America learns more about what it means to be transgender, Beck says even she is still trying to figure out some aspects for herself.

"It took me a long time to get to this point where I'm comfortable living in my own skin," she says. "I'm very comfortable living the way I'm living right now, because it's natural to me now, and I've never had that."

What she seems sure of is, "I'm not a gay man, I'm not a drag queen, I am not maybe total dude, and I'm not total feminine, I'm not totally female," Beck said. "I think I'm living more in that gray world."