A conservative man is often ready to marry earlier, and a smart conservative gal will pick up on that and make it possible.
Then they have to work out the inevitable changes that take place in any life, and grow together, or grow apart.
The best reliable indicator of being able to sustain a long marriage is similarity in age, class, and values (including spiritual).
If you pick a partner from a messed-up home, hoping to bring about a "rescue"--beware. Children of the dysfunctional marriage tend to create dysfunctional marriages.
I also agree with the assertion that many, many women have a neurotic masochistic streak. This can also emerge in women's relationships with other women, so I don't see how it can be denied, any more than men can deny how many of them struggle with a neurotic attraction to those far younger than them.