Today, my parents have been married 40 years. That's a pretty long time, especially when you compare it to the fact that Noah only spent 40 DAYS on the ark.
I can't imagine my parents forty years ago, but they must have existed. Many things did not exist then-- like rollerblades, or cell phones, or pesky computer security that makes you change your password every three months to some new code that has a lower case, and an upper case, and a number-- even if you can't possibly invent 4 such complex codes a year. My parents have been married the equivalent of 160 online banking passcodes.
Marriage, as a long-term endeavor, is somewhat antiquated by modern standards. But, between love and rollerblading, the former is certainly more challenging, and forty years of continual effort is impressive indeed.