Meh, I don't really see the point in putting too much stock in the notion of marriage. Granted, you don't have to do much research to know just how marriages fail here in the U.S.; and the hundred+ reasons why it happened. However, judging from what I've seen, I think people take it too seriously. In this respect, it's not so strange to see people grow into the opinion that marriage is more of a burden then they imagined; and, should this happen, it's also a predictable course that said person will look for an outlet to relieve some of that burden.
I'm not saying it doesn't have its up-sides, but it just seems like too much thinking has to be put into it to really enjoy it. I say just nix the whole thing and enjoy your life as best you can with your significant other.