ORLANDO, Fla. -

The estranged wife of George Zimmerman says she thinks her husband has unraveled since he was acquitted in the fatal shooting of Trayvon Martin.

Shellie Zimmerman said on Katie Couric's show "Katie" on Thursday that after his murder trial, he had become unpredictable and "a pacing lion."

Shellie Zimmerman says she doesn't think her husband intended to kill the 17-year-old Martin. He said he fired his gun in self-defense. Martin was an unarmed black teenager and his death set off protests nationwide by people who believed he was racially profiled by Zimmerman. Shellie Zimmerman said she did not think her estranged husband is racist.

Since his trial, Zimmerman has had several brushes with the law, including an arrest this week on charges that he threatened his girlfriend with a gun.