During the long on-air chat with Howard Stern on his radio show Wednesday, Arquette, 39, said that his psychologist, whom he sees once a week, believes he's having a "nervous breakdown."
"I've been drinking a lot," said Arquette. "[But I don't] want to go into all that, because it's really a personal, traumatic thing."
"Everybody's worried and concerned about me," he added. "When I drink, I become a maniac."
Arquette said his alcohol use had gotten out of hand so he's "definitely not drinking for a long time."
Of his split from Cox, 46, Arquette said, "This is the hardest thing anyone has to go through … You wake up and the reality hits you."
He added: "[Courteney] said she doesn't want to be my mother. I kind of need a mother right now. I need a girl to come bring me some soup and make sure I'm all right. I like that, and I take care of my ladies, too."