A lot of people complain about the depressive attitude of some gay stories, but they forget that a lot of it served as social commentary or came straight from the authors experiences with society, especially older ones.
I'm no expert on yuri and have a very narrow reading of it, but it has a similar history with being targeted for censorship in Japan during the war period, so relationships were depicted as more ephemeral. Though of course, people were writing more idealized and fantasized yuri fiction, and sometimes more dramatic and tragic, than this particular manga.