Is it wonderful if two couple stays together even there is just a little or nothing that binds them?

I am amaze about some couple whom a partner could not bear a child but they remain together despite of it. To couples who have far different businesses that is willing to compromise just to be together. Couple that is willing to go far to understand and meet differences. I believe that kids needs the parents to work hand in hand in forming a family. Papers that states couple that it is legal to practice cohabitation..but what about the absence of offspring or papers? Was it just enough reason to leave and give up if the relationship goes messy? Leave the partner because you have no kids..Leave the partner because there is no paper? If kids are there and because papers entitles you, the only that holds you to stay together, so be it? What is partnership if there is no love? Is it forsaken at all?...