Just found out yet another couple I know are splitting up :( 4 dc, married for 6 years.
I know its all to do with brain chemicals and clever sciency stuff, but surely if we could stay as happy and loved up as we are at the beginning relationships would be so much more fun. And people wouldn't split up! Because they would be happy.
Definitely Probably naive of me I know.
And am sure lots of smug possibly deluded mners will be along soon to tell me all about how they have been married 30 years and are still in the honeymoon phase..... 
I have only been with DH 5 years and while we are generally very happy I do miss that electric lust filled phase of the early days, where everything the other one does is Just Amazing...IMO scientists ought to invent a love drug to be taken every day after the first 18 months.