The Question and Answer section for The Darling is a great resource to ask questions, find answers, and discuss the novel.
One major theme in Chekhov's story is the nature of love. This theme is illustrated through the character of Olga Semyonovna, who lives for the idea of love and withers away without it. In the story, however, Chekov questions Olga's feelings about...
I think lacking personal conviction and a sense of identity is at play here. Olga lets her convictions and independence change to accommodate the opinions of whatever man she is with.
Olga's first marriage ends when he husband dies unexpectedly in Moscow.