LONDON: Chris Brown has acknowledged his attack on Rihanna has "damaged" the pop star for life.

Brown split from the Bajan beauty in February (09) after he assaulted her in a vicious fight that landed him a community service order and five years probation.

The Umbrella hitmaker returned to the spotlight last month (Nov09), finally speaking out about how her life has changed since the altercation - and now Brown admits it's clear how much his ex-girlfriend has struggled.

He says, "I can see what damage it does, mentally, more than physical... I was wrong for what I did. And I would definitely say that it's not something that I look past or look over. Something that's really, really touchy. And, and like I said, I'm really sorry for what went down. And what happened."

But the Kiss Kiss hitmaker insists the criticism he's received for appearing happy and moving on with his career is unfair - because he is still deeply tormented by the incident.

He adds, "I think what it is when people see me smiling and kind of nonchalantly getting answers or, or saying things. I'm human, really, I'm like really hurting inside. And it really is devastating to me."

Brown's comments will be aired in an interview with U.S. news show 20/20 on Friday