Love never demands something that will harm you or the person you love. Love will never cross the line between what's right and wrong. It's wrong to put one another in danger of having to deal with hard choices. Having sex before marriage may feel right for the moment. But the possible costs of an unexpected pregnancy, abortion, and sexually transmitted disease as well as the deep hurts that can come from a broken relationship outweigh the feelings of the moment.
All good things are worth waiting for.
Waiting until marriage to have sex is a mature decision to control your desires. There are two ways to respond to this question. One is to explain why contraception goes against God's plan for sex, even in marriage. Sex is for deepening love between a husband and wife and for the procreation of children. God intended for these two purposes to be inseparable.