The great danger for family life, in the midst of any society whose idols are pleasure, comfort, and independence, lies in the fact that people close their hearts and become selfish.  St. John Paul II
St. John Paul II said that the greatest destroyer of love in marriage is selfishness. It is one of the 12 marriage killers described by Richard Fitzgibbons in his book Habits for a Healthy Marriage: A Handbook for Catholic Couples. Fitzgibbons says that developing virtue is the antidote to these unhealthy habits in marriage.
“Selfishness is the major enemy of married love and of life-long commitment in marriage” (57), says Fitzgibbons. St. John Paul II warned about selfishness in his 1994 Letter to Families Gratissimam Sane…
Selfishness in all its forms is directly and radically opposed to the civilization of love.
Fitzgibbons states that “behaviors that indicate selfishness include attempting to control others, harboring excessive anger, having an intense sense of superiority, and manifesting strong levels of aggressiveness when challenged” (58). He goes on to describe other symptoms that psychiatrists have identified for individuals for whom “selfishness is a serious personality disorder…exploitation of others, manipulativeness, deceitfulness, callousness, irresponsibility, impulsivity, emotional lability [exaggerated changes in mood or affect in quick succession], risk taking, lack of empathy, and incapacity of intimate relationships” (58). Fitzgibbons provides an extensive checklist to help couples understand if their relationship is affected by selfishness (59-60).
Fitzgibbons says “self-giving is essential to human fulfillment and happiness” (60). Citing John Paul II’s apostolic letter On the Dignity and Vocation of Women, “the call to self-giving is realized in marriage” (60):
The fact that man “created as man and woman” is the image of God means not only that each of them individually is like God, as a rational and free being. It also means that man and woman, created as a “unity of the two” in their common humanity, are called to live in a communion of love, and in this way to mirror in the world the communion of love that is in God, through which the Three Persons love each other in the intimate mystery of the one divine life.
Fitzgibbons stressed that the “failure of spouses to give themselves completely to each other can result in sadness, anger, mistrust, anxiety, loss of confidence, and various compulsive behaviors…[and]…can also contribute to the development of depression in…the neglected spouse” (61). He goes on to describe how such selfishness also is harmful to children and the church.
Fitzgibbons says that cultivating the virtue of generosity in marriage is the antidote to selfishness. Citing a 2013 study on marital happiness, He states that “generosity, as defined by small acts of kindness, displays of respect and affection, and a willingness to forgive faults and failings, was positively associated with marital satisfaction and negatively associated with marital conflict and perceived likelihood of divorce” (54-55).
We highly recommend Fitzgibbons book to both engaged and married couples. Virtues are the foundation of a strong and happy marriage. In writing this book, Fitzgibbons seeks to “help couples to identify and resolve the major conflicts that weaken their relationships” while providing “a deep Catholic understanding of marriage, which is essential for strengthening marital love” (19). Fitzgibbons has 40 years experience as a psychiatrist and has counseled hundreds of couples, families, and youth. This book can be read in its entirety or couples can focus on the areas that are particularly troublesome in their relationship.
 John Paul II, Holy Mass at The Capital Mall, Homily of His Holiness John Paul II.; October 7, 1979; internet: http://w2.vatican.va/content/john-paul-ii/en/homilies/1979/documents/hf_jp-ii_hom_19791007_usa-washington.html (accessed September 15, 2019).
 Richard P. Fitzgibbons, M.D., Habits for a Healthy Marriage: A Handbook for Catholic Couples, (San Francisco: Ignatius Press, 2019).
 John Paul II, Letter to Families Gratissimam Sane, §14; internet: https://w2.vatican.va/content/john-paul-ii/en/letters/1994/documents/hf_jp-ii_let_02021994_families.html (accessed September 15, 2019).
 John Paul II, Apostolic Letter Mulieris Dignitatum (On the Dignity and Vocation of Women), §7; internet: http://w2.vatican.va/content/john-paul-ii/en/apost_letters/1988/documents/hf_jp-ii_apl_19880815_mulieris-dignitatem.html (accessed September 15, 2019).
 Fitzgibbons citing Jeffery Dew and W. Bradford Wilcox, “Generosity and the Maintenance of Marital Quality”, Journal of Marriage and Family 15 (September 3, 2013): 1218-28, https://doi.org/IO.III/jomf.12066.