So, what you are saying, is that France will put its own interests before the interests of the other EU countries that might benefit from trade with the UK?
As a non-French member of the EU, I will fully support France in their decision (and hope my nation takes a similar route).
The UK never believed in the EU and only wanted the good side of it. It's better for everyone that they'll be gone. There was no European Union if a selfish state didn't want to be united in the bad things too.
If the EU as a whole decides for a new trade agreement with the UK, that's fine (See? Unity), but I think they won't since the EU has strong motivation to slap back the UK.
Great for European unity, I see.