Nope.
The fundamental principle of the 'Leave' campaign's argument that the EU needs us more than the UK needs us is that we run an £80m trade deficit with the European Union. This is true, but it is not the entire picture.
The EU makes up about 45% of the UK's exports - a percentage which the 'Leave' campaign is right to emphasise as a declining percentage, but nonetheless it still makes the EU by far the largest importer of the UK's goods. On the other hand, the UK makes up just 7% of the rest of the EU's exports. Therefore, if a 'Leave' vote would threaten the ease of trade movement through leaving the Single Market (as is quite likely), 1 in 2 UK goods
could no longer be able to sell to their previous consumers - compared to about 1 in 20 EU goods.
The entity that comes out worse off is evidently the UK and not the EU: they are much more important to us than we are important to them. Both would inevitably suffer, but the UK would do so far more.
What about Germany? In 2015, the UK was Germany's third-largest trading partner - £68bn of German goods were exported to the UK in 2015. The UK, on the other hand, exported £29bn to Germany (
source). By these numbers, Germany would suffer more than the UK - but this forgets the fact that Germany's economy relies on the UK's economy much less than the UK's economy relies on Germany. In rank order, the UK is the 9th largest exporter to Germany after countries like China (1st), the United States (4th) and Poland (6th).
However, the UK exports more to Germany than it does to
any other country - and unlike Germany, it hasn't built up such great trade relations outside of the European Union (this is a failing of national government and not the European Union, seeing as Germany is subject to as many EU trade regulations as we are). There is an argument, therefore, that the UK would suffer more than Germany because it would lose a greater percentage of its exports even though Germany could lose up to £39bn in trade relations.
Either way, Germany wouldn't go "bust". There would be negative economic impacts on both sides, but a 'Remain' campaigner would argue probably more so on the UK's side: the German economy is well-fitted to change exporter away from the UK because the UK isn't as important an exporter as other countries are to Germany, but the UK's economy - on the other hand - is far more reliant on Germany and on trading within the European Union.