May I recommend an Authorised Naturist Beach relatively close to St Malo, Normandy, France.
Maybe it will help if I say that Saint-Germain-sur-Ay is about 85kms north of the town of Avranches, which is itself east of St Malo. Google gives a driving time between Avranches and the beach as 1 hour 20 minutes, a pleasant and relatively easy drive.
See http://www.nude-france.com/St-Germain-sur-Ay.htm
I don’t seem to be able to get links to the maps to work but Google maps clearly show the area. The beach was easy to find and the local naturist society have erected direction signs in the vicinity.
The beach is huge, much larger than Morfa Dyffryn, and on the hot and sunny day we visited there were only 5 or 6 cars in the free car park. The short walk across the dunes to get to the beach is clearly marked.
In keeping with the number of parked cars were the number of people using the beach; a dozen at the maximum and those who passed us exchanged friendly greetings.
I would suggest so extensive is the beach that if a couple were visiting and one was a little more bashful than the other, the reserved partner would very quickly feel at ease.
In the village of St-Germain there is a small supermarket and I believe a largish café (not sure on that as didn’t actually use it). From memory there seemed to be a few other shops too.
One word of warning (which I guess applies to many beaches with huge tide differences, I think I’m correct in saying that the difference between high and low tide at nearby Le Mont-Saint-Michel, a not to be missed tourist attraction, is one of the greatest in the world). But when the sea goes so far out it’s bound to leave sandbanks and on one of these we left our clothes/cameras/drinks and the like. But then playing around in the very warm sea we suddenly realised the sandbank was about to be submerged and it was a rapid gallop to retrieve our clothes. But having done so we then had to swim or wade through deep water to get back to the beach, so BEAR IT IN MIND.
Should you decide to visit scan the beach for a bald headed old fella whose stomach muscles have decided to relax in the past few years, as that will be ME for one day I’d love to return.
Ken