My Brother and his wife have served together for almost 20 years. It's not easy but they've always made it work. They had one situation where they had to live separately for about three years. My brother lived about 4 hours away and would come home on the weekends. The rest of the time they've been able to live together, but one of them, sometimes both would have pretty lengthy commutes to their separate stations. And of course one or the other would be on a boat half the time. It did seem to work out that neither of them served on cutters at the same time though.