(CNN) 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."

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Trapped in a man's body

It chronicles her life as a young boy and man, known then as Chris Beck.

Beck deployed 13 times, serving in places such as Bosnia, Afghanistan and Iraq. She earned a Bronze Star and a Purple Heart along the way.

Though she's felt trapped in the wrong body since grade school, Beck didn't come out until after she left the military in 2011.

Doing so earlier would have been too big a risk.

Transgender men and women are banned from service.

"That's a chance that if I took it, I might be dead today," she said.

"There's 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."

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 explains 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 said.

"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."

There's a lot of prejudice out there. Kristin Beck

Looking back, 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 career, Beck kept her mouth shut.

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

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

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."