Just finished this. Came across it in a charity shop, clear eyed, non sentimental diary of a woman in Berlin when the city fell. Having read a few books of the 'Berlin Noir' genre I think this was possibly a big influence for their authors.
Similarly a few years ago came across 'Alone in Berlin' as ex-library stock, now a film. I found it a slog to start with but then it caught me and off I went. As you're on this forum I suspect both of these will interest you.