I would certainly check into this idea more before you make too many plans. I lived in France for a couple of years and knew an American physician who now practices over there (French spouse, same as you). He finished his MD in the states before his wife decided she couldn't stand the states any longer and moved. He had to repeat some of Med School in France. I don't know how much you know of their system, but from what I recall, it is a 6- or 7-year program, and at least for this particular man, he had to repeat selected years of that program (3, I think) before he could continue with his training and practice.
This may have changed since, but it is certainly something that would motivate me to check into the current policies.