Just as when a thirsty man, in his sleep, attempts to take a drink but the moisture needed to extinguish the fire in his limbs is no where to be found; so instead he looks for images of liquids and struggles in vain and drinking in the middle of a roaring river he is still thirsty. In the same way, Venus, in matters of the heart, teases lovers with images; and these lovers, even when face to face and looking at one another’s actual bodies, can’t satisfy themselves; and even when their hands are wandering hesitantly over one another’s body they are not able to scrape off anything of their lover’s tender limbs. And when, at last, with limbs entwined, they enjoy the fruit of their age, and when their bodies are on the point of ecstasy, and Venus is on the edge of sowing the woman’s field, they greedily join their bodies and mix together the saliva of their mouths, and breathing into each other they press teeth on mouths. But all this is in vain since they are still not able to scrape off anything from each other, or to penetrate one another or to enter completely into one another—body into body; they often seem to not only want this but they also struggle to do this. And so they longingly cling together in the bonds of Love and, shaken by the force of their pleasure, their limbs melt away. Finally, when the desire, mounting from their pleasure, bursts forth, there is a brief pause in this violent passion at least for a little. But once again, this same madness returns and that fury revisits them. When they are desirous and look to hold onto something—but they aren’t sure what—they are unable to find a way to conquer the ache. And so,uncertain, they waste away from this mysterious wound.
My reading of Sade and a recent thread from @Noxrpm on Twitter inspired me to spend some time translating this section of De Rerum Natura.