Fonsia and Weller are two characters with great energy and vitality, and they seek each other out. I definitely think there is a sexual component to their relationship, for good and for bad. And we've pointed that up in our production.
Although he'll never acknowledge it, Weller sees himself as a loser in life. Nothing has worked out the way he imagined. He touched on success and it was yanked away from him. As he is challenged by Fonsia's character later in the play, he sees himself as a victim. Therefore, the game becomes the all-important opportunity to win at something in his life.
Fonsia keeps coming back to that card game, where she gets yelled at and treated fairly badly by Weller, because she needs it as much as he does. What brings them together are the same things that drive them apart: The energy, the repressed anger, the sense that neither trusts the opposite sex. For all of Fonsia's well-bred, lady-like demeanor, her emotions are very close to the surface. So are Weller's. These people are hurting, and as they get deeper into a relationship, they don't try to hide their anger or pain.
Fonsia's anger is equal to Weller's, but her anger is much more successfully hidden. Fonsia seems to represent many women of her era, who were brought up to believe that they would function as wives and mothers in a certain fashion. They were unprepared for the betrayals that hit them in life.