Chris Brown views hitting Rihanna as his "biggest mistake".
The 23-year-old R&B singer assaulted the 25-year-old Bajan pop star in 2009.
He was subsequently prosecuted and put on probation for his crime.
The pair have recently rekindled their romance, with Rihanna choosing to spend her February 20 birthday with her beau in Hawaii.
At Elton John's AIDS Foundation 21st annual Academy Awards Viewing party, which was held in West Hollywood Park on Sunday, Chris revealed how he has transformed since the infamous battering.
"Sometimes you row, you fight, with the one you love and things get said, stuff spirals," he told British newspaper The Mirror.
"That night was the deepest regret of my life, the biggest mistake.
"But she loves me – what can I say? I'm forgiven… but, yes, I worked hard for it."
Chris is very aware of the widespread public outrage about his and Rihanna's relationship.
He doesn't care what other folks think.
"People attack me and criticise me, it happens all the time," Chris explained.
"But they don't know me, and they don't know us. It doesn't bother me any more.
"Other people can judge us but they don't know anything."
The musician assures that he has matured immensely since that brutal incident.
Chris thanks his loved ones for getting him through rough times.
"I've learned a lot since that night and I've grown up. I was very young and I took a lot of stuff, fame, for granted," he said.
"I didn't understand it. The support from those who do know me and the fans, who are incredible, got me through."