Yes, we feel safe in Marigot in the afternoon. Don't know the answer about the laundry though. YEARS ago there used to be one in the Village, but I know that one is not there anymore.
There's also a self do laundromat in Grand Case. Enter as you would go to the school, go past the school and it is in a building on your right.Used to be able to drop off laundry and have them do it, but no more.
If life hands you a lemon, just squeeze it on a lobster!