I knew I must be missing something. What you are referring to is in being so settled that you are stuck in a rut and it's not so great. (did I get it right this time?) I was married for 20 years and I know what that feels like. I learned that you can try to pump sunshine up your butt all you want, but if the other person doesn't try to make it better too, it is futile. I do beleive that if you introduce a different atmosphere (like an unusual vacation) it can add a level of excitement that opens you both to new experiences that you can explore and find that joy again. However, the risk is that the other person doesn't want to play and it winds up being a catastrophy and makes matters worse.