What do you think it takes to be married to one person for that long?
Maybe it's shared interests. They both like playing board games, like Triominos. Neither will play Scrabble with me anymore. Neither of them enjoy having their ass handed to them by their progeny. They've stood up to my vocabulary and word placement skillz and said, "No more!"
Maybe it's the ability to communicate their feelings and needs using "I" statements.
No, that's not it.
Could be all the stuff they do that I'm not privy to. Not just the stuff that any self respecting child doesn't want to think about their parents doing (but used to hear them doing anyway) but all the stuff that is their marriage and no one else's marriage. Their methods and their madness. Marriage as they've made it. Every day.
Yup, that's probably it.
Couldn't replicate that if I tried, what the two of them are together. I have to make it to fifty years in my own marriage on our own steam in our own way.
That and maybe I'll buy a can of Aqua Net just for insurance.