Less than a week after In Touch exclusively confirmed her engagement, Jessica Simpson celebrated her upcoming nuptials with friends, family and, of course, her fianc�, Eric Johnson, at her parents' Encino, Calif., estate on November 18. The bride-to-be's mother, Tina, threw a casual party with pizza and finger foods from La Loggia Italian Bistro and roses from Mark's Garden for 50 guests, including Jessica's sister, Ashlee, her brother-in-law, Pete Wentz, and her best friend, CaCee Cobb. "Jessica and Eric looked so happy," an insider tells In Touch. Not all was smooth sailing, however -- the singer, who along with her former football player beau arrived two hours late for the soiree, seemed anxious for guests' approval of her unique ruby engagement ring. "At one point, she asked one of the servers what she thought of the ring. When the server said it was beautiful, Jessica snapped, 'You don't mean that!'" the insider says. But all in all, the blond beauty enjoyed her celebration. "Jessica is in love," the insider adds, "and kept talking about her wedding plans and new life with Eric."