I think a good wife is a happy wife.
The same as with a good husband. Its really draining to be around someone who complains all the time.
When things arent ideal it helps to have a sense of humour I think, rather than reach for the whine.
I have observed that though poor couples can struggle, they keep together for families sake, richer couples have more to lose but find it easier to separate, maybe cos they are not so financially dependent on each other.
A lot of people, especially young people, simply marry in order to leave home...they dont want to stay there, maybe they dont get on with their parents at all, and someone comes with a proposal or better offer of a home than they already have. At first you wonder why they got married to someone so unsuitable who maybe doesnt even like them. But then you look at their family life and background and then you can put two and two together.