The Marquise de Merteuil is a self-described, self-made woman. She writes that she is her own creator. As a young girl Merteuil refused to let fate or society describe her, and began to compose herself. After her husband died, she set about educating herself and creating a reputation. Since then, she has remained at the top of the heap through careful manipulation, never once letting her guard down.
The Marquise is not particularly interested in love, nor does she seem to believe that love exists except as that capacity men and women have to enslave each other. Though she admits that it is possible that she and the Vicomte de Valmont once loved each other, she seems to have no interest in renewing that affair even when the opportunity presents itself.
As a letter writer, she is shrewd, with a particular gift for lifting phrases out of other people's letters and using their words as if they were her own. This nasty side of her self-protective instinct is reflected in her downfall. The disease that disfigures her has an interesting result: other people's true opinions of her are, metaphorically, written on her face.
Like the Marquise de Merteuil, the Vicomte de Valmont is in it for the game. Or at least, he professes to be, and he styles himself as a player, without any belief or trust in love.
Valmont employs a repetition, or parody, of other writers' styles throughout his writing. As he seduces her, the Présidente de Tourvel's religious tones begin to appear in his letters. The Vicomte adopts the Présidente's language in order to convince her, but this also tends to alter what he says. Therefore, he must subvert Tourvel's religious motifs to his own purpose with parody, just as he must subvert her religious convictions.
But Valmont's pride is also his downfall. So impressed by his former immunity to love, he cannot admit to himself that he has found a source of happiness in the Présidente de Tourvel. He is unable to allow himself to see that the game is over, and so he sacrifices the Présidente to the dictates of intrigue, and ruins himself as he has ruined so many women before.
Religious motifs surround Tourvel. She is often described as praying, or as having the air of prayer about her. Her letters are also full of religious imagery. She seems to take everything she does, and her motivations for what she does, to heart. After Valmont leaves her, the metaphor of lost faith and lost chastity casts itself over Tourvel's entire physical being, so that the sadness and regret she feels in her mind becomes manifest in her body. Just as Cécile decides to become a nun and wear a veil to repent for her adultery with Valmont, the Présidente must let her body die to expiate her misdeeds.