It's not 'morbid friendship', it's realpolitik..
Not anymore and not necessarily. Not in time of weapons of mass destruction. Geo-strategic penalties that Russia pays within Slavic world and globally are already much higher then any gain Russia could get from Germany on the other side. That same Germany makes Russia looks like a fool from Baltic to Balkan.
So, why is that realpolitik? And plus in era when Russia have strategic partnership with China? In a blink of an eye Russia can isolate Germany in any sense and then overrun it. You think Britain and the USA would enter global war because of Germany, you are wrong.
Whether it was all those pre-1871 individual German states as part of the Empire..... time for wars and conflict are past
In past was different. Religion had enormous impact on people. Vatican played on Germany while Poland was entirely Catholic. Russia couldn`t trust to Poland and at the same time had to counter-balance general Vatican`s influence that inspired Drang Nach Osten. There was France, too, that had to be contained.
Same reasons why Russia entered alliance with Austria. Plus, Turks were player in Europe/Balkan that had to be tackled in any possible way.
Now is different time. But far from it time of conflict is past. Its naive to tell it.