Lust is what makes you keep wanting to do it, even when you have no desire to be with each other. Love is what makes you keep wanting to be with each other, even when you have no desire to do it.

Viorst’s aphorism draws a sharp, practical distinction between sexual appetite and enduring attachment. “Lust” is framed as a self-renewing urge toward the act itself—desire that can persist even when emotional closeness or companionship is absent. “Love,” by contrast, is defined as a commitment to the person: the wish to remain together even when sexual desire ebbs. The pairing suggests that long-term intimacy is not measured by constant passion but by the preference for shared life, mutual presence, and loyalty through fluctuating desire. It also implies that mature relationships integrate both forces, but that love is the sturdier basis for staying.