I just love this:

Adam revels in the goodness of Eve’s very existence, just as she revels in the goodness of his; it is as if they said to each other: “It is good that you exist and that we exist together.” It’s only when lovers recognize this depth dimension in each other that their love becomes hardy enough to outlast changes in their feelings or alterations in their qualities and attributes.

From Called to Love: Approaching John Paul II’s Theology of the Body

Related: To Love is to Create Anew