General de Gaulle was right in the 60s that the brits are more trouble than they're worth. France is smart and won't let them back in. Brexit is now and forever as far as the EU is concerned.
The guy who famously received safety for himself and his family in Britain during the war, what a thanks indeed... Believe it or not I've heard this anecdote told as a projection of anti-European sentiment, have you considered what might have been for the Anglo-European relationship had he not felt France was the centre of the European project and portrayed the UK this way?
De Gaulle also wanted to shield the nascent EEC from the United States's influence as much as possible. For him, integrating the United Kingdom into the EEC would have moved the EEC's barycenter too far towards Washington.