Interesting question. We had been dating for a few months before we really discussed it.
She had been married once before at a young age to an unstable fellow who turned out to be an alcoholic disaster. And had a few relationships with men which hadn’t worked out: one cheated constantly, another was a religious fanatic who also let money slip through his fingers like water (credit cards constantly maxed out, etc).
When we met she was thinking of moving back from California to the East coast to be ‘closer to her sister’. Who actually turned out to be a complete asshole who who didn’t give a shit about her… but that’s another story.
In fact we finally realized that what we both really wanted was a stable, respectful marriage… as we’d in fact grown up in as children. And that’s what we have, decades later.
Of course we share much of the same sense of humor… that may be more important than many other factors….