Courteney Cox -- Divorce Papers Don't Surprise Me

Courteney Cox didn't sit at home and mope after news of her divorce broke yesterday -- instead she went out to dinner with friends in Malibu ... and blew off the split like it was no big deal.

Cox hit up Nobu with her daughter Coco and another mother/daughter combo ... possibly to celebrate their birthdays (Court is June 15 and Coco is June 13).

When we asked about David's decision to file the divorce papers Friday ... even though he filled out the docs back in March ... Cox smiled and sarcastically replied, "He diiiiid? Oh my god, I didn't know."