Actors, models, singers, directors, even some writers travel a lot. They spend months away from home at times. If a woman is celebrity and her husband isn't, it's easier to manage the schedule, the man can travel with his wife. Though even then, the man might find it too tiring after a while and want to settle down somewhere instead of going from one place to another all the time, or when they have a child, one of them will have to stay with the kids so they can go to school. This might cause a lot of problems like the lack of sex, not getting emotional support in person, and not feeling like you're married when you actually are. And when two celebrities are married, they both have a busy schedule. When one of them is giving a concert in Paris, the other one has to give a concert or promote a movie in New York
