dogstile said:
Maybe because satisfying the primal urges to actually be with a mate is still important to society and is indeed important for the survival of a species, therefore great importance is still placed upon said finding of mate.
Just sayin' ;D
If you want to talk about "primal urges, you might be interested to know that (according to "science"), primal humans were
serial monogamists. This means that we originally tended to be monogamous with one person at a time, but had several mates throughout our lives (well, as many as you can have when you only live to 20). So even if the biology places importance on finding a mate, the idea that any one person will "complete" you isn't necessarily part of that.
Personally, I think this whole long-term monogamy thing has more to do with property arrangements and the challenges of raising children in modern civilization than it does with the human makeup.
Edit: More from observation than experience, I think you're going to do a lot better in a relationship if you feel complete
before you go looking for that special someone. Thinking that companionship will "complete" you is setting yourself up for strained relationships and bad breakups.