"Could be that if Merkel is history then so is the EU. That is a little more than pure speculation!"

The EU isn't a Merkel-construct, it existed for a very long time before Angela Merkel became the German Chancellor. Why should her falling from her position in the German government cause the EU to implode? She is but one person.

The British lunatics leaving is, I would have thought, far more likely to have a deleterious effect on the stability of the EU.