Jody and Mel have a great relationship. Following Jody's terrible ordeal of being abandoned by her former husband, Wayne, with an infant son, Mel steps into her life and not only develops a close relationship with Mel's son, Will, but also wants to marry Jody and move to New York City, where she would able to further her career as a photographer.
Wayne and Corky, on the other hand, have a troubled relationship, predominantly because Wayne simply isn't a nice guy. Our first indication of Wayne's difficult nature, apart from him walking out on his wife and newborn son, is that he is not looking forward to have his son come and visit. Corky, eager for a child of her own, uses Will's visit to showcase her mothering skills, but Wayne is far more interested in having an affair with a wealthy client.
I'd argue that Wayne falls into some of the more old-fashioned stereotypes when it comes to gender roles. He is self-absorbed, uncaring and only interested in his next thrill. Jody, on the other hand, is every inch the independent, progressive woman. She even hesitates to marry Mel, as she is nervous of giving up her freedom and independence.