Being in the couple adds to their lives, but is not their lives. They do not try to be close to their partner at all times. They do not share every detail of their lives past or present with their partner. They have privacy. Many women have trouble with this aspect.
Men have a tradition of a night out with the boys.
Women, especially working women with children, have so many duties and responsibilities that they don't feel they have time. Women are more conditioned to see their lives in terms of their relationships, especially their spouse or partner. Lesbian women tend to have trouble because they see each other as one another's total support system. Improvement here is tied to other aspects. Re-distribute responsibilities so that you have time carved out to pursue your own interests and friendships.