First, the battle is in your heart and mind, but it cannot remain there. We lust because our hearts are crooked. We crave that young man’s attention because we are covetous. So we must work on reshaping our desires. But that does not mean we ignore the dangers around us. Learn to identify your lusts. But also learn to identify those things outside of you that inflame your lusts. In other words, work on your heart, but do not ignore practical ways of avoiding temptation.
Second, you have a lot less self-control than you think. Proverbs 7:26 says that those who fall prey to the harlot are many (ESV) or strong (NKJV). In either version you get the point. You are not above falling. Get too close and you will get burned. Pride is one of the great slayers of men. Often sexual sin is one of chief ways it slays us.
Third, emotional closeness and physical closeness are meant to go hand in hand. You cannot grow in emotional intimacy with someone of the opposite sex without also growing in your desire to be close physically. Excluding family members, you should be careful in getting too close emotionally with members of the opposite sex.
Fourth, intimacy outside of marriage does not prepare you for intimacy within marriage. The world believes that to have a good marriage you must go on several “test drives” before choosing your car. This is a lie of the Devil. A one night stand is nothing like sleeping with the same woman every night for 50 years. Kissing that young man in the backseat is nothing like kissing the same man every morning and every night for 50 years. Skipping from dating relationship to dating relationship is nothing like being committed to the same person for decades.
Fifth, intimacy without real commitment does not prepare you for marriage. By this, I mean pornography, online chatting, flirtatious relationships at work, long phone conversations with members of the opposite sex, one night stands, casual dating, etc. These situations do not involve real obligations or they involve minor obligations that do not parallel the obligations that come with marriage. Some of these things are held up as getting you ready for marriage. That is a lie. Not only do these types of relationships not prepare you for marriage, they often prepare you for divorce.
Sixth, marriage does not automatically fix an undisciplined life. Our minds deceive us when we think, “That porn habit will disappear when I have a real woman.” Or “I will stop flirting with the guys when I have someone to take care of me.” No you won’t. Work on that sin right now. Marriage is not an automatic sexual disinfectant.