In the 1950's and before, a female was pretty much expected to marry right out of high school, or maybe work for a year and then marry, or maybe (even weirder) to enter college to find the "right man" and then marry. The major expectation was marriage and the purpose was to have children.
Then, in the 60's women started the fight for equal rights in all things, including the right put off marriage until they wanted to as well as to to be employed outside the home EVEN after having children. This allowed 2 parent families to "have more stuff" because instead of only one income, there were now 2 incomes. I am a child of the 50's. My mom started to work outside our home when I was about 7 years old. My 2 older sisters had the responsibility of watching out for me. Because Mom worked, we were able to buy more stuff (an additional car (never new)), nicer clothes and we moved and got a bigger house.
By the time I got married, it was considered uncommon for a woman to 1) have children right away (she was expected to want a career and a child would interfere), 2) to stop working IF she had children. It was considered normal to pop out the child and be back at work in 6 to 8 weeks, with the kid placed with a family member if they were available OR in a child care facility (which was UNHEARD of in the 1950's!
Fast forward to the 2000's and such.... it is considered normal for a female to either 1) go to college after high school, or 2) go in the military after high school, or 3) get a job and work after high school. There is no expectation that a woman gets married anymore. There is no expectation that a marriage will LAST anymore either.