[1] https://www.gutzitiert.de/zitat_autor_oscar_wilde_1481.html
I've lived here for three years, with a native speaking partner; but it's just not happening much.
Before that I spent three years in school studying German, all gone.
I don't like the language very much, I guess that could be part of the difficulty. It's just too damn complicated, the same way C++ is complicated.
Interesting comparison. I find computer languages incredibly easy to pickup. Human languages on the other hand have been much more difficult. I only speak English and sometimes even then my words come out in the wrong order or I forget words entirely (+).
(+) I once forgot the word "and" - as a result I struggled for a day to speak/write many complex sentences.
Selig sind die, die nichts zu sagen haben und trotzdem schweigen
(And google also found something I assume is a singular version: "zu sagen hat und trotzdem schwiegt")
[0] http://events-stg.clasadvising.arizona.edu/nichts-zu-sagen-z... , last paragraph at the time I looked.