Marie said in the wedding documentary that during the years she lived in Geneva she went skiing any weekend in winter. Plus she owns a dog and Geneva is a lakeside town with a pleasant climate, so Marie probably had daily sunshine on her face..
Remember that Mary was tanned, too when she came to Denmark but how fast that changed? It might be different with Marie as she lives closer to the sea and could take walks with their dogs daily at the coast, so getting more UV than Mary in Copenhagen, but still - the South of Denmark is not the South of Switzerland when it comes to the intensity of sunshine.
If you are using protective facial creams and get you tan from doing sports under the real sun, then at Marie's age you normally are not sun damaged, especially not if you are a Franco-Latin-type like she is.