Love is a commitment of the will to the true good of the other person. You can t promise to have a feeling. Consider procreation again. In every other biological function, such as eating, digesting and growing, the man and woman are separate organisms. For procreation, they join to become a single unit, functioning in covenantal harmony.
Conjugal union is a true merging.
They become a one-flesh unity and I m not just talking about their bodies. When I say that I m not just talking about their bodies, I mean that at every level, male and female were designed to complete each other. In sexual self-giving, the hearts and minds and spirits of the husband and wife cooperate with their bodies. They are united not just in their bodily dimension, but in every dimension. This unity also helps prepare them to be parents, and the hope of children joins them in solidarity with every past and future generation.