Looks and falling in love

People claim that the looks is an important factor when we fall in love. But still most people are married to someone who isn't beautiful and hardly would become a model. There must be something else that determines with whom we fall in love, if the looks are as important as people say.

Have you heard about something called marital likeness? When I've been sitting and waiting for someone and just looking at strangers passing by, I have noticed that many couples with kids have similar face details, as if they were brothers and sisters and not couples!

Maybe it is easier to fall in love with someone if he or she feels familiar, and has some resemblance with a family member or a dear friend or some famous person or even a previous partner.

How else can we explain the completely different tastes when it comes to looks?

(I'm curious. I would like to know...)