Since we know that romantic love escalates within a functionally isolated, closed brain system and that the caudate nucleus would be the crucial brain region in the evolution of love, it is suggested that the hormonal
products of pineal gland may attenuate the romantic love through the anti-dopaminergic and inhibitory effects of theirs on the nucleus. This mechanism might turn out useful in early stages of romantic love to “cure” the infatuation. This means it may be possible to attenuate it by external administration of the melatonin and vasotocin (Shoja, Tubbs, Ansarin, 2007).

This hypothesis sounds somehow promising since Helen Fisher‘s research shows that almost 95% of men and women asked reports being dumped by someone they really loved.

Sources:

Shoja, Mohammadali, M., Tubbs, R. Shane; Ansarin, Khalil, (2007). A cure for infatuation?: The potential
‘therapeutic’ role of pineal gland products such as melatonin and vasotocin in attenuating romantic love. Medical Hypotheses, Volume 68, Issue:5, pp.1172-1173.

Fisher, Helen, (2005). Why We Love? The Nature and Chemistry of Romantic Love. Henry Holt and Company, New York.