For more than 25 years, David Schroer was a star in the U.S. Army, rising through the ranks to become a Special Forces Commander while leading a classified anti-terrorism unit involved in covert operations. Fellow soldiers described him as a classic military man.
That all changed two years ago when he abruptly retired from the military and made a shocking announcement that stunned his colleagues and family alike. He would no longer be Col. David Schroer, because he is now Diane Schroer, a transsexual.
In her first television interview, Schroer explains to "20/20" correspondent Deborah Roberts why, after decades of service in one of the most dangerous and macho lines of work, she became a woman.
"Does seem a bit of a disconnect," Schroer acknowledges. But, she says, she has struggled with her gender identity -- privately -- since childhood.
"Something was different since even before I can remember. I was always enthralled with things the girls were doing. ... Whenever my parents were gone, I would experiment with my mother's makeup. And wondered why I enjoyed doing that... Wondered why I couldn't carry a purse," Schroer tells Roberts.
Schroer's family has come to accept her decision, but she is now embroiled in a gender discrimination lawsuit against the Library of Congress, which, she claims, withdrew its offer of employment based on her sex.
Her lawsuit may be precedent-setting, but Dr. George Brown, a military psychiatrist, said Schroer's story is not unique. He said he's treated hundreds of soldiers who are transsexuals. Brown described transsexualism as "a sense that there's been a biological mistake -- that the body doesn't match who you are as a person inside."
Schroer says it was apparent to her from the time she was a child, growing up in Oak Lawn, Ill., just outside Chicago. Her brothers, Gary and Bill, only remember a happy childhood with their little brother, however.
"I think it was probably very much...the typical American family, three boys growing up. We played baseball. We played in the neighborhood. We rode bikes. We pretty much did what other kids did in the '50s," said Bill Schroer.
Schroer's siblings never knew their little brother was suffering quietly, never daring to mention the anguish inside.
Schroer says growing up as a boy left her feeling uneasy and deeply conflicted about who she really was. "When I hit adolescence, it was at times consuming. ... So I did everything I could to push that out of my mind," she tells Roberts.
When David Schroer entered Northern Illinois University, he was in full denial of his gender crisis. He worked as an auto mechanic, an electrician and joined ROTC. After graduation, he entered Special Forces and somehow thrived in the most dangerous of military careers. He even fell in love with a woman and got married.
"We had a normal sexual relationship," Schroer tells Roberts. "Although I would say that I would often think of myself being on the other side of the relationship."
Schroer managed to keep up the act, rising through the ranks of the military. By his mid-40s, he was a Special Forces commander leading a classified anti-terrorism unit and managing an $8 billion budget. He even briefed Vice Dick President Cheney on secret missions.
Then, two years ago, he grew tired of denying what he believed was his true sexual identity.