If anything Elsie can see that Lena is in control of the marriage and not Strudwarden. Strudwarden is arguing with Lena over where they should go on holidays.
Munro had a penchant for mocking the popular customs and manners of Edwardian England.
Munro never married and may have been gay, but homosexuality was a crime in Britain during Munro's lifetime and the decorum of the times would have required him to keep that part of his life secreted away. Throughout the story Lena shows an independent and determined streak.
The story includes many of the author's favorite themes: good intentions gone awry, the banality of polite society, the attraction of the sinister, and the allure of the wild and the forbidden.