Before setting down any moral principle, two things must be considered: The first is that steady dating or company-keeping has for its purpose marriage.
This does not mean that two persons who date will necessarily get married.
In "Love and Responsibility," Pope John Paul II emphasized that, since men are more visually attracted, women must consider male psychology when deciding how to dress.
They are keeping company whether they admit to it or not.They should receive the sacraments often, and they must avoid circumstances and intimacies that they know would tempt them gravely to sin.It is useless to pray to God to remove the obstacle to the marriage while living in sin. Sometimes also the couple will put off the marriage for foolish reasons.This inclination is there to help them in the right and favorable circumstances to enter into marriage where their inclination can be virtuously satisfied, i.e., in accordance with God's plan for the propagation of the human race.But it is clear that our inclination cannot recognize God's plan.