Another poster said it... because we are social creatures. Not to mention, the idea of social groups and companionship is very much dealt with and talked about all of the time in the media and in our society as a whole. Because really, what is the meaning of life if you don't have people to share it with?

In a way... we have been conditioned that our lot in life is to go through school all the way up until we finish college, find a wife or husband or life partner, have a great job, maybe some kids... etc. Because that is what is depicted as "normal" behavior.

The truth is... (and I have only found this out since being married and having kids), there is a lot of happiness to be had by being single and rockin' your single status. Because it is at that point in your life that you only have to deal with yourself. And it is an opportunity for you to really understand who you are and what you want out of life. Those are good things to figure out before getting married.