Chris Brown says his "deepest regret" was the event that led to the brutal fight with Rihanna in 2009.

Brown told the UK Mirror, "Sometimes you row, you fight, with the one you love and things get said, stuff spirals."

If you want to read more on this article and see what else Chris Brown has to say about Rihanna you can find the article here http://www.tmz.com/2013/02/26/chris-brown-regret-rihanna-deepest-regret/ 

but until then I guess it's really nobody's business. Check out the song below