Multiple Personality Disorder

In popculture depictions of multiple personality disorder, 90% of the time, patients were women. A book comes out in th 19 50 is called the three faces of eve. It describes a woman named Eve who has two personalities - slut and nice housewife. In mid century America, how can you have sex on purpose, except to be a slut? Yes, there's just no way to have sex unless you have an alternate personality.