Correct on the point about the husband’s income.
The expectation of marriage is the key driver of the sexes’ wage gap, which is created by both women AND men. Look at this way:
Suppose a law prohibited men, in marriage and out, from supporting women, spending money on them, and giving them assets of any form that are convertible to cash.
What kind of work decisions would women make? What kind would men make? Explore the influence on both married women and single women of a husband’s income (or a future husband’s income), and you’ll see why there is a gender wage gap.
To see how better off women as a group are relative to men, see:
“Salary Secrecy — Discrimination Against Women?” http://malemattersusa.wordpress.com/2014/10/27/salary-secrecy-discrimination-against-women/