We just sort of lost touch with how much we cared for each other. It can be difficult to anticipate all the changes that follow the birth of a baby. Expectant parents often read and learn about the physical and emotional realities of parenting an infant, but they may not expect that their own relationship will change so much. Understanding what's going on can help parents cope with the challenges of first-year parenting. Many family therapists today use a method called Systems Theory.
Systems theory provides a framework for the family to use when looking at their problems.
It likens human relationships to a thermostat. We become used to a relationship working in a certain pattern. This is like setting the thermostat. When anything in the relationship changes, it causes us to shift. It is like opening a window or cooking something in the oven.