Germany's economy depends a lot on exports by exiting the Euro Germany would take a huge hit in that regard possibly causing a recession. That along with the obvious conflict in political goals makes this a scenario that no one in Germany will ever seriously consider.
Besides at the moment Germany is one of the most if not actually the most powerful country in the world (economically speaking). Germany currently controls the future of the Euro and with that a big part of the future of the EU and the world economy. Why give up that power?
And I was under the impression that the US has much more economic power than German. Or China with its billion+ people market.
The Euro is the attempt to balance this power with an European currency. The market of the Eurozone is the sum of the countries and Germany is a part of that. Germany alone is relatively small (a market of just 80+ million people - compare that to the US, China, ...).
Besides at the moment Germany is one of the most if not actually the most powerful country in the world (economically speaking). Germany currently controls the future of the Euro and with that a big part of the future of the EU and the world economy. Why give up that power?