The case continues to stoke racial tensions across the country. Many speakers cited the case during commemorations of the 50th anniversary of Martin Luther King Jr.'s "I Have a Dream Speech" in Washington last month.
Martin, who was black, was unarmed as he walked back to the home of his father's fiance after going to the store. Zimmerman, who identifies as Hispanic and was a neighbourhood watchman, began following Martin because he thought the teenager was acting suspiciously. He says he shot the Martin in self-defence during a fight.
In the interview, Shellie Zimmerman revealed she wasn't at their home the night of Martin's shooting because she'd had a fight with her husband.
"I was staying at my father's house," she said. "We had gotten into an argument the night before and I left."
Shellie Zimmerman says that while she believes her husband's version of the events leading to the shooting, "I can't tell you how many nights I've gone or laid awake at night just thinking that I wish to God the circumstances had been different."
She says the couple lived in hiding while awaiting his trial.
Shellie Zimmerman admitted she did not tell the truth during the bail hearing.
"I can rationalise a lot of reasons for why I was misleading, but the truth is that I knew I was lying," she said.
She said she plans to do her community service with a Christian ministry.
"I've made mistakes and I want to own them right now," Shellie Zimmerman said.
She also told ABC she is deeply sorry for the Martin family's loss. "I can't even begin to understand the grief a parent experiences when they lose a child," she said.
- AP