So, a guy goes to visit a friend from college, ten years have passed, they now live in different towns, both married. In the evening they go out in a bar, and the 'visitor' starts looking around and trying to pick up some ladies. The host is somewhat surprised, but they haven't seen each-other in a long time, maybe his marriage sucks...
Few weeks pass and now the other friend decides to visit. To his shock, the wife looks simply stunning. She's also nice, smart, takes good care of the home, and is a brilliant cook. Everything about her seems perfect. They sit to have dinner and, after having their favorite lamb chops the now visiting friend asks his host "WTF are you doing cheating on your wife, she's the best?" to which the other responds "wait for a week and you'll see".
As the week goes by, an odd thing happens, the loved lamb is being served every day, it's the only thing to eat actually. It's as good as always... but every day? Then, on the last day of the visit, suddenly there's bean soup - as plain as it gets. Then, when the friends are about to part, the host says "I askedy wife to make lamb every day, so now you know, even having the best meal you can imagine every day gets boring, from time to time you need something different, be it just beans"
I'm not sure about the moral of the story... just that my wife hates it when I tell it :)