First things first: most sociology majors won't earn as much money as STEM majors, post-graduation. But when you're choosing a major, it's important to follow your interests as well as considering money. The study of human behavior, how people interact within different structures, and how people relate to each other, is utterly fascinating to many people. If this rings true for you, than majoring in sociology could be a path to consider.
Way back when, marriage was a necessity for women. They needed a husband to sign for a loan, job security (yes employers looked at marriage status) and, in general, to achieve upward mobility. Now that the union more of an emotional and social connection than an economic partnership, more women eschew holy matrimony in favor of independence. These days, there's just not as much demand for husbands.