You're assuming the woman doesn't work, but I don't remember reading that. You're also assuming she put her career on hold, but a lot of careers are not location-specific. A woman could have moved to a city where her man is going to grad school and taken a job. At least that's the only way I've ever heard it. The school application process gives both parties the time to do the planning necessary. So I imagine that if a woman plans to move with her man for 2-3 years, she would launch a job search in every city where he's applying to school. Or, once he gets accepted, which is like 6-9 months before classes start, then she'd start her job search then. At least that would be the smart thing to do in such a situation.
I should also add that having the flexibility to move cities for a man requires that a woman has transferable skills. It's just easier/she'll have more options. If a woman is following a man around doing entry level jobs the entire time, she'll never grow in her career. Still gotta watch out for yourself.
Anyway, I remember this anecdote a former law school student told me. She said that she was living with her fiance (I don't remember if he'd moved for her), but that it became clear pretty early on that she couldn't fall into the student lifestyle if she wanted to maintain the relationship: working all night, having all the study sessions, not devoting time to the relationship. She said she decided to treat law school like it's a job. She went on campus by 8, took all her classes and did her homework and everything by around 5pm. Then she'd go home and relax and spend time with her fiancé. Basically to not disrupt the routine they'd established pre- law school.
I was 21 when she told me that. The story stuck with me because I was so impressed with her efficiency. She was at Harvard Law, and when I met her she'd just graduated, and the law firm that hired her didn't have enough business for her to start right away, so the firm was paying her for 1 year, while she's not working, and then she would officially start later. Those last few details are not relevant to the story, but just wanted to add them because I was bloooown away by this unicorn situation lol.