Sean Penn's past movie career feels like "a dream" - because he's been so focused on the relief effort in Haiti for the past two years.

The Milk star set up the J/P Haitian Relief Organization in the aftermath of the devastating 2010 earthquake, and has helped thousands of needy families rebuild their lives.

Penn has largely taken a step back from movies to concentrate on the charity, and he admits his focus is still on helping Haitians.

He tells CNN chat show host Piers Morgan, "It is very strange now. With Haiti, that experience makes much of my prior career kind of a dream in some ways. We just, yesterday, one of our staff was in Haiti... has been just a hero... (he) was killed. This young man.

"What we all thought about, all of us involved in the organization and those with whom he worked and so on, is like 30 years of movies has been this last two years in Haiti and all the flashes, of course, beginning with his face, his smile, all of that - him helping people.

"It's as if, after Haiti, that all of what had once been (in my movie career)... (I feel) proud in some ways and deeply ashamed at other times, of a kind of flash reel of one's career, you know. And the creative part of it and those things, all of that stuff, I think the part of my brain that used to hold onto it got filled with this, this other reel, over the last two years somehow."

But Penn insists he won't turn his back on a Hollywood career completely: "I still have a love affair with the movies. I prefer directing movies than to act in movies."