Kṛṣṇa tells Arjuna, His disciple, that “It is lust only … which is the all devouring, sinful enemy of this world.” [Bg. 3.37] In the Vedic language there is no word for materialistic “love”, as we call it in the present day. The word kama describes lust or material desire, not love, but the word which we find in the Vedas for actual love is prema, meaning one’s love of God only. Outside of loving God there is no possibility of loving. Rather, there is lusty desire only. Within this atmosphere of matter, the entire range of human activities-and not only every activity of human beings but all living entities-is based upon, given impetus and thus polluted by sex desire, the attraction between male and female. For that sex life, the whole universe is spinning around-and suffering! That is the harsh truth. So-called love here means that “you gratify my senses, I’ll gratify your senses,” and as soon as that gratification stops, immediately there is divorce, separation, quarrel, and hatred. So many things are going on under this false conception of love. Actual love means love of God, Kṛṣṇa.
Everyone wants to repose his loving tendency in some object which is in his opinion worthy. But the question is one of ignorance only, because people have a poor fund of knowledge about where to find that supreme lovable object who is actually worthy to accept and reciprocate their love. People simply do not know. There is no proper information. As soon as you have some attachment for anything material, it will kick you upon the face, deteriorate, and disappoint you. It’s bound to dissatisfy and frustrate you.
In material consciousness we are trying to love that which is not at all lovable. We give our love to dogs and cats, running the risk that at the time of death we may think of them and consequently take birth in a family of cats or dogs. Thus love that does not have Kṛṣṇa as its object leads downward. It is not that Kṛṣṇa or God is something obscure or something that only a few chosen people can attain. Caitanya Mahaprabhu informs us that in every country and in every scripture there is some hint of love of Godhead. Unfortunately no one knows what love of Godhead actually is. The Vedic scriptures; however, are different in that they can direct the individual in the proper way to love God. Other scriptures do not give information on how one can love God, nor do they actually define or describe what or who the Godhead actually is. Although they officially promote love of Godhead, they have no idea how to execute it.
The loving affairs between Kṛṣṇa and the gopis in Vrndavana are also transcendental. They appear as ordinary lusty affairs of this material world, but there is a gulf of difference. In the material world there may be the temporary awakening of lust, but it disappears after so-called satisfaction. In the spiritual world the love between the gopis and Kṛṣṇa is constantly increasing. That is the difference between transcendental love and material lust. The lust, or so-called love, arising out of this body is as temporary as the body itself, but the love arising from the eternal soul in the spiritual world is on the spiritual platform, and that love is also eternal. Therefore Kṛṣṇa is addressed as the ever green Cupid.
Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “The Science of Self-Realization”, Page 299, 310
A.C. Bhaktivedanta Swami Prabhupada (2012 edition), “Teachings of Lord Caitanya, The Golden Avatara”, Page 11, 360