One of the universal themes that this excerpt expresses is that of a desire for freedom. This is a desire that all humans have, and one that can make social commitments or social relationships difficult.
In this excerpt, Mrs. Mallard thinks about what it means to be left without a husband. Her first thought is how she will no longer have to act according to anyone's will. She believes that whether this is done out of a good or a cruel intention, in the end it still shows a type of control that a person should not be entitled to have over another one.