04/07/2012 at 03:05 PM EDT
Transgender Miss Universe Canada contestant
Jenna Talackova says that even at four years old, she knew she was "in the wrong body."
In her first interview since she was booted from – then allowed back into
– the Miss Universe Canada competition for not being a "naturally born female," Talackova sat down with ABC News's Barbara Walters on Friday's 20/20
Accompanied by her mother and her lawyer, Gloria Allred, the beauty revealed that at birth, she was named "Walter."
Talackova, 23, who was called "tranny" and "it" by bullies at school, started hormone therapy at 14. Later, she underwent gender reassignment surgery to convert her male genitalia to female.
"It was terribly painful," Talackova told Walters of the procedure, "but seeing something on your body for that long and not being able to look at myself in the mirror because I couldn't stand seeing the other part, it was actually very rewarding, too."
To complete her physical transformation, Talackova also received breast implants and had her Adam’s apple removed. Her legal transformation became complete after she changed her Canadian driver's license, passport and birth certificate to reflect her gender reassignment.
She is now recognized as female by the Canadian government, and lives a full life as a heterosexual woman – and even has a boyfriend, a man she says is near her age and is "very supportive … just an amazing man."
And she's taken the beauty pageant controversy and turned it into an opportunity to help pave the way for other women like her.
"I feel like the universe, the creator just put me in this position as an advocate an advocate
, she told Walters. "And now it's like this, and I'll take that position. If it's helping anybody else, my story and my actions, then I feel great about it."
The Miss Universe Canada pageant takes place May 19.