Every time I meet East Germans, the discussion will inevitably touch the unification and the social tension.
What I heard were complaints on
* privatization by the West and sometimes closure of enterprises. People of age 40 and older remember well the tough years after unification when their parents had no job and had to take a lower-level one.
* they claim that management of states and enterprises was taken over by the Wessies
* a lot of complaints about amerikanization of the culture and aligning with the US in every international policy question under Merkel. I regret I did not ask further about the culture, but just an example: by default radio stations in Germany put American music, more than stations in other Western European countries that I heard. It's very hard to stumble upon songs in German, just as any other language but English. (If you listen to French stations, foreign non-English music is much more probable to hear.)
* East Germans are more atomized and secular. That's similar to other East European contries.
* Women were forced to emansipate in the East, because they needed to work, whereas in the West they could afford being housewifes. And a surprising consequence, in the West a man can't be friends with a married woman -- Ossies living in the West complained of that too.
That's what I've heard from them and some my own superficial impressions from radio. I can't confirm that, but sure it's more or less founded info.