Some people are not called to be married. Their call is to the single life.
It is important that society does not create a burden for those who are not married by failing to respect the single life. Unfortunately, a society that does not respect chastity and continence can neither respect celibacy, and so today those who choose to live a celibate single life are mocked by society.
In this sense, those called to the single life support the married state, as by living out a chaste life they show that chastity is also to be valued (and is essential) in the married life.
The reality is that every single human being has lived the single life at some point of their lives. No-one is born married. Thus we should respect a state of life that we have all lived.
The single life is too called to fruitfulness.
Those called to the single life can make a “gift of self” to the service of society in a way that is not possible for those who have family responsibilities.
The single life is not an excuse for selfishness. Single people are called to make “a sincere gift of self” just as any other human being is called to do.
Prayer for vocation to the Single Life:
"Lord Jesus Christ, who didst embrace the single life whilst thou wast on earth; grant grace to men and women called to service of thee in the single state, that they may dedicate themselves to service of thy kingdom, who livest and reignest with the Father, in the unity of the Holy Ghost, one God, world without end. Amen."