Oscar Pistorius Weeps Through Apology to Reeva Steenkamp's Family

"I was simply trying to protect Reeva," he tells the court.

PRETORIA, South Africa April 7, 2014— -- Oscar Pistorius spent an emotional day on stand today crying repeatedly, apologizing to the family of his slain girlfriend Reeva Steenkamp and eventually asking to quit early because he was emotionally and physically exhausted.

Today was the first time Pistorius has publicly discussed the night that he shot Steenkamp through a locked bathroom door on Valentine's Day 2013. He claims he mistook her for an intruder. If convicted of premeditated murder he could be sentenced to at least 25 years in prison.

Pistorius, 27, struggled to keep his composure during his testimony, crying a times and other times speaking so low through a wavering voice that the judge politely asked him to speak up. When the judge asked if he was on medication, Pistorius said yes. Others in the courtroom also cried during Pistorius' testimony.

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He began his long awaited account by apologizing to Steenkamp's family.

"There hasn’t been a moment since since this tragedy happened that I haven’t thought about your family. I wake up every morning and you’re the first people I think of, you’re the first people I pray for. I can’t imagine that the pain and sorrow and the emptiness that I caused you and your family," he said.

"I was simply trying to protect Reeva. I can promise that when she went to bed that night she felt loved. I’ve tried to put my words on paper many many times to write to you but no words would ever suffice," Pistorius said.

Reeva Steenkamp's mother sat stone-faced in the courtroom.

The legless paralympian known as the Blade Runner told the court that he is haunted by her death and that his love affair with guns is over.

"I’m scared to sleep.... I have terrible nightmares about things that happened that night where I wake up and I can smell, I can smell the blood and I wake up to being terrified... I wake up in a complete state of terror, to a point that I’d rather not sleep than fall asleep and wake up like that."

Pistorius told the judge that he has "lost a significant amount of weight."

He said that he is on anti-depressants and takes sleeping pills.

Pistorius, who owned several guns and used to sleep with one, says he doesn't want to touch a gun again. Instead, a security man stands outside his door, he testified.

In talking about his childhood he said his mother slept with a firearm tucked inside a padded bag underneath her pillow.

"She often got scared at night. We didn't live in the best of areas. There was a lot of crime. She would call the police, call us to her room and we would wait for the police to arrive," he said.

At Pistorius' request, he was not shown on the court's camera, but the audio was carried. His lawyer eventually asked the court to cut short the day's testimony because of exhaustion.

His lawyer led Pistorius through testimony showing that he had an awareness of crime occurring to others. Twice, Pistorius testified, he intervened to rescue someone who was being attacked, using his gun to scare off a trio of men beating a cab driver with rocks, he said.

Pistorius also recounted a 2009 boat accident that left him with a smashed face and forced doctors to put him in an induced coma.

"I was a lot more vigilant of losing my life after that. I became quite fearful, I became quite withdrawn," he testified.

Pistorius, who has been seen fingering a rosary during the trial and underlining sections of a religious book, said that Steenkamp "was a very good Christian."

"She would pray about my traveling and all of the small things in my life," he said through tears as he broke down crying again towards the end of the day's testimony.

"My religion is what's gotten me through this last year... my God is my refuge," he said.

Pistorius was preceded to the stand by Professor Jan Botha, a retired pathologist who testified for the defense.

Botha insisted the state pathologist's findings that Steenkamp had eaten no more than two hours before her death cannot be accepted. Pistorius has claimed that he and Steenkamp went to bed about 10 p.m. The prosecution's claim that Steenkamp had eaten about 11 p.m. would contradict Pistorius' timeline of events.