Poly relationships exist.

Actually yes. Read some more articles, they decided to marry him and his family agreed.

And you decide that for the people you don't know based on your system of values, that is the only that is true, right?

So much hypocrisy in letting some people decide what to do with their bodies and their life and prohibiting others to do the same. Marriage can exist only between two people in the most of the world. And I haven't heard anything about abolishing this outdated concept.