Hubby and I have always done this from the very first. We don't speak badly of one another in front of our parents or friends, we're even careful how we joke about each other. I knew a lady years ago and all she did was berate her husband to anyone who would listen, in front of him!! I always felt so sorry for that poor man.
Of course, it is best if husband and wife can attain to never speaking badly of each other
any at all - not even in private - because they truly understand, and never forget, the two-become-one reality that God put into place. And, they love each other enough to
not want to [so much as] belittle the one they treasure.
Anyone who speaks badly of their spouse to someone else is not thinking clearly, being selfish, or worse.