the cradle
by rantywoman
And finally, if there is one attitude that women alone urgently need to change within themselves, it is their presumption they will marry and stay married. Women should plan from youth as if they might never marry; they should see this not as a bleak fate but as an expansion of possibilities that opens worlds, not closes them. If indeed maturity can be measured by the degree to which one attempts to perceive reality (a definition that appeals to me), then most women who stay deliberately blind to the possible prospects of divorce or widowhood have not yet moved out of their cradles.
–Patricia O’Brien, The Woman Alone, p. 222
thebitterbabe 
I don’t think we do women any favors by undermining the fulfilment found in marriage and motherhood. Most women are still looking for these things even if they’re not always fun and games. (A great career isn’t always fun and games, either!) I feel bad for women who are older and were told that marriage and children are secondary to getting into a great career. But we should not do a disservice to younger women by refusing to acknowledge our mistakes and by refusing to show them the error of our ways.
The woman who wrote the book was married with kids but took time away from her family to live alone and pursue a career. She later returned to her family.
I don’t think she is saying that family is secondary to career but that some time as an independent woman is a good thing. For me, marriage would have been ideal between 28 and 32. Unfortunately it does get harder to find someone then. But that’s what would have been ideal for me because I enjoyed my time of independence, travel, etc.
As you say, it may begin to get harder for a woman to find someone as she gets older. And ending up alone or without children or struggling with fertility can be hard on a person. So maybe we should let younger women know it in no uncertain terms. Decades ago this stuff was probably common knowledge.