"I need to get through this I need something inside of me get through this!"
He revealed he purchased a gun after Caylee's disappearance.
He said, "I wanted to go get answers that I believed I could get from individuals responsible for Caylee."
"You were going to force them at gunpoint?" asked Casey's defense lawyer, Jose Baez.
After Caylee's body was found, George says he tried to commit suicide by taking an overdose of prescription drugs.
"I needed at that time to go and be with Caylee because I believe I failed her!" he explained.
He said he had always believed Caylee would be found alive. "Every day from July 15th until the day we were told it was Caylee," he said tearfully.
As he broke down, Casey shook her head in shocked disbelief.
True Crime's Aphrodite Jones was in court.
"There were people in the audience who were crying. Jurors were on the edge of their seats. They were poker-faced but you could see that there was anxiety, there was tension, and yet, through it all, Casey Anthony was like stone," Jones says.
George Anthony oscillated between tears and anger as he battled with his daughter's lawyer.
"My family was being torn apart and for you to say that I was doing something wrong, sir, you're wrong!" George told Baez.
And he was defiant when Baez accused him of sexually molesting Casey when she was a child.
"I never would do anything like that to my daughter," he said.
"You know of course that sex with a child under the age of 12 years old is life in prison, don't you, sir? […] You of course would never admit to it, would you, sir?" Baez asked.
"Sir, I would never do anything to harm my daughter in that way," replied George.
Baez accused him of trying to "throw Casey under a bus" by claiming a bad smell in Casey's car was human decomposition.
George said, "I can close my eyes at the moment, sir, and I can smell that again. How dare you, sir, try to tell me that I did something differently than what I did."
"And that is why you called 911 right then and there, right?" said Baez.
"No, sir, I did not call 911. I didn't want to believe back then that my daughter could be capable of taking the life of her daughter," George answered.
After a grueling ordeal on the stand he seemed emotionally exhausted and had to be helped out of court by his attorney.
Jones says, "There is no question that George Anthony's testimony today was extremely damaging to Casey Anthony."