Well, if both work (apart from all the work inside a home), what happens if a working woman runs off with another person? I see no difference.
Oh yes there is, unless the woman has worked full time all of her married life. The man generally (not always) leaves the children behind or undertakes a limited amount of childcare; he probably earns a higher salary whereas she, because of child responsibilities has not pursued her career as high as the husband, or built up the same pension pot.
Divorcees are described as the new poor; a comfortable life suddenly upended, loss of home, less income, more expenditure, and much less time to earn sufficient money.
I am aware this is not entirely the case and more women are better equipped for the single life, as are men, but it is a sad reflection on our times.