Romantic love both exhilarates and motivates us. It is also critical to the continuation of our species. Without the attachment of romantic love, we would live in an entirely different society that more closely resembled some (but not all) of those social circles in the animal world. The chemicals that race around in our brain when we're in love serve several purposes, and the primary goal is the continuation of our species. Those chemicals are what make us want to form families and have children. Once we have children, those chemicals change to encourage us to stay together to raise those children. So in a sense, love really is a chemical addiction that occurs to keep us reproducing.
Regardless of the country or culture, romantic love plays an important part. While cultural differences in how that love is displayed vary greatly, the fact that romantic love exists is undisputed.
But let's get down to the nitty gritty. What is it that makes us fall in love with someone in the first place?