Campbell explains how men and women go through depression during thier forties. He writes:
Perhaps the most common cause of depression is a conflict between objective reality and an individual’s beliefs and desires. The so-called ‘mid-life crisis’ of many men is depression caused by the realization that their career plans are not going to work out. The big house with the big pool and the sports car and the boat are not going to happen: the dreams of being department chair or CEO have gone, and many men do not want to accept a role in life or a position at work that is unrewarding and unimpressive.
Housewives become depressed when household chores offer little fulfillment, and they long to escape further years of boredom. But career women who believed the feminist promise of fulfillment through independence, singleness, and career success also now write articles about depression. Reality is different from dreams. With a physical basis in PMS and menopause, a woman’s depression often has a mixture of physical and spiritual elements due to reacting inappropriately to these circumstances.
Individuals who succumb to addictions are often depressed. Seeking happiness or relief through alcohol, sex, money, drugs, gambling, or food becomes a habit, and the conflict between what is and what should be causes feelings of worthlessness, guilt, and self-contempt.
Source: Campbell, K. (1996). Those ugly emotions: How to manage your emotions (42). Ross-shire, GB.: Christian Focus Publications.