Le Baron,
I don't see it as melancholy as much as 'realism'.
Have you read Thérèse Desqueyroux by Mauriac, François, 1885-1970? That is not realism. The main character is Thérèse and she is clinically depressed. No other words for it.
I get your point re realism, however, clinical depression is clinical depression.
Of course, the French write happy stuff; absolutely, but just not in their literature of the 20-21st century.
Michel Houellebecq is renowned for his depression in his books.
And I don't believe you are suggesting the Dostoevsky was a realist are you?
I don't mean to mischaracterize your words. Melancholy is a part of life; I totally agree, however the way these authors handle it, it is the plat du jour of a one course meal of life.
Or so it seems to me....