Gossip Girl's Matthew Settle Finds Marital Split Tough

Having separated from his wife of four years, Israeli actress-model Naama Nativ, in February – and coping with his situation with the help of his also recently separated costar Kelly Rutherford – Gossip Girl's Matthew Settle tells PEOPLE, "I'm not enjoying it … it's tough."

Speaking at Thursday's Lilly Pulitzer-sponsored dance at New York's American Museum of Natural History, Settle, 40, said, "Until the divorce is over, it's tough to know how much time I’m going to spend with [1-year-old daughter] Aven and how the chips are going to fall. So I hope for the best."

Moving forward, "I think that we'll be good co-parents," he says. "And we'll do the best we can."