LOVE and Marriage

So I was thinking about love and marriage ( reminds me of the old Frank Sinatra song)the other day and I realised there is a trend. First one, divorce rate is the largest it has ever been before at 50%! It is almost disturbing how common divorce nowadays and how I can only think of about 5 or 6 of my friends, whose parents are happily married,(not including those whose parents have gotten remarried). Divorce is certainly not something to be taken lightly; especially with kids.
I feel, well marriage is just a contract. There are exciting parts of the deal and not so exciting parts of the deal. But ultimately, marriage is something people are just doing, its as if people left and right are getting married or engaged. And some even get engaged for months or years, what is the point of that?
Also Is if marriage is a natural thing? Are we supposed to be with the same person for the rest of our lives?So what is the point of marriage if 1 out of 2 happy couples are choosing to ruin their perfectly good relationship?
I'm guessing there is sense of financial security, you have someone who will do anything in the world for you,Children... but all of these things can happen without a contract and getting married.
To me all that really changes is your last name. Who knows though when your in love you will do anything for your partner!