It seems clear that the two words have the same origin, yet pathetic and pathetisch seem to have significantly different meanings (or don't they?).
Pathetic is very negative with synonyms like pitiful, miserable, disgraceful, shameful, despicable, dishonorable etc. Whereas pathetisch is not necessarily negative, as it just means excessively dramatic or emotional. They do however show up as translations of each other, though usually being somewhere a bit further down on the list.
So first of all, what is the common ground that these two seem to have, how different are they in meaning? When and why did the meanings change? Have they once been used synonymously and if so, which meaning came first?