The notion of "Love" is a concept which people have created and shaped over the centuries in order to feel good about their reproductive urges and behaviors, on both individual and collective levels. The concept of "Love" helps us validate our mating urges, intentions and committments, making them socially acceptable and justifiable. "Love" is an ideal that serves as a cohesive force in society to ensure continued matings and also the raising of offspring.
I'd also be willing to bet that "love" has its hormonal roots. Since women seem to pine away about love more than men, it's very possible that there is a female hormone responsible for "love", of which men do have, but in lesser amounts.
And if you take away "love", take away the feel-good hormone? We become nothing but breeding cockroaches. And from present global census figures, it's very easy to conclude that our species behaves like swarming cockroaches anyway, love or no love. We swarm and rape the earth, exhausting natural resources, leading to pollution and overcrowding in urban areas, and yet we still have not the slightest interest in curbing our reproductive impulses. We are only selfish, mammalian cockroaches with big brains, women and men alike.