Rubbing, touching, caressing, kissing, sucking, biting, and, of course, intercourse, as fulfillments of a desire for physical contact, are all sexual activities in this sense. When one merely has sex, one perceives the other as an object of pleasure, as Kant describes. They can reflect tenderness; an adoring or adorable look; or the instant when you knew you wanted to be together for an eternity. In making love, there is thus a virtually seamless reciprocity between I-It and I-Thou. But instantaneously each becomes Thou again with co-mingling of not just body but soul. There is resignation of separateness to inclusion of the other. My past, present, and future; my hopes, dreams , and expectation; and yours, coalesce as one--not two--persons. Accordingly, it is essentially this unifying aspect of the activity of love-making that largely distinguishes it from mere sex. But while this mutual sexual agreement whether inside or outside the context of marriage may be a precursor to love-making, the latter takes more than mutual consent to let each other satisfy a sexual desire. The flames of love-making are quick to die when one gives oneself, body and soul, only to be turned away. There is also powerful symbolism in love-making as depicted. As such, making love is inspirational, for it signifies and embodies two mutually living as one. To get a handle on an answer to this question you might consider what I have had to say in my blog on How good are you at making love? According to philosopher Alan Goldman, sexual desire is desire for contact with another person's body and for the pleasure which such contact produces; sexual activity is activity which tends to fulfill such desire of the agent. For, like religious experience, love-making has an element of faith. For I suspect that many people make love well before if ever they are actually in love. It is an ecstatic resonance that defies any breach in Oneness.