Dear John:

If you are called to the single life then live your life as a good and loyal Catholic, doing all the things that a devout Catholic is suppose to do -- which is what we are all to do.

A calling to the single life means that you feel that God is calling you to remain single and not seek religious life, the priesthood, or marriage. This means that God is calling you to remain celibate and chaste in perfect continence (that means, no marriage, and no sex) without becoming a religious or priest.

Since the vocation to single life is not a formally vowed vocation, though you can write up personal vows for yourself it you wish, or take vows in a third order (see below). In the single life, of course, you can change you mind any time you feel called to do so.

I would recommend the books, Introduction to the Devout Life by St. Francis de Sales, the Exercises of St. Ignatius Loyola, 12 Steps to Holiness and Salvation by St. Alphonsus Liguori, and Back to Virtue:: Traditional Moral Wisdom for Modern Moral Confusion by Peter Kreeft for starters.

Also see if there is a third order you can join. I really do not recommend the O.Carms (Lay Order of Carmelites), but the OCDS (Secular Order of Discalced Carmelites) are excellent. There is also a Secular Franciscan Order.  If you are near a monastery you can check there about being an Oblate.

God Bless,
Bro. Ignatius Mary