Time and entropy (empires dissolving or population groups migrating) definitely diffuse the responsibility for a horrific act. Of which there are many in history. But this specific thing happened in living memory, was performed by an organization that still exists (a German speaking nation state, with almost the same borders as before), and by people the OP knows personally. In fact, it's a very wealthy nation that OP has gained a lot of advantage from living in. It's subjective and graduated, but I don't think it's been nearly "long" enough that the Holocaust just background noise next to all other events that have happened in human history.
Modern Germany is awesome btw. Really respect how they've reckoned with this awful time in their history.
There is no point getting depressed from one's ancestors past - if one looks in the past far enough, there will be probably something utterly horrible that given nation/tribe/group did to somebody innocent. Basically all western european democracies fall into this category, and many, many other nations too.
Don't forget about it by any means, tech your kids as I will do, but don't put emotions into this just because your nation was the culprit. There were similar things happening to innocent civilians en masse in the past elsewhere. Genocides are not an invention of Germany or 20th century, life was often pretty horrible and violent in the past.