"I've always been a wild man," the actor, 39, told George Lopez on Tuesday's Lopez Tonight. "My nickname was 'David Good Times.' I like running around, having fun."
He added: "I like meeting people. I did that privately for a long time because I wasn't ever going out. Now, I'm in the nightclub business. I'm going out."
Arquette, who spent last weekend partying very publicly in Miami, says he doesn't care what the tabloids say about him. "I am a fun-loving, great person," he says. "I refuse to let these magazines vilify me, make me a demon. I am one of the best people you'll ever meet."
He added: "I've always been wild and crazy ... why don't we all start focusing on being cooler ... like loving, caring people. I'm just sick of cutthroat society and everybody being jerks."
Cox, 46, recently spoke about the couple's separation after 11 years of marriage, saying they are not getting divorced. "This is a separation and I think that takes a lot of courage," she said. "Whatever is supposed to happen will be the best thing for us."