How do different techniques help the reader to better understand the outsider theme in Mansfield's "Miss Brill?"

One way in which the "outsider" theme is brought out is
through Mansfield's narration.  Miss Brill is seen as functioning in the world, but she
is not a part of it.  She does not interact with anyone or with anything of value.  The
narration allows the reader to fully understand that she is an outsider because she lies
outside the reach of what is happening in the world.  She moves through with ease,
primarily because she is not a member of this world with any relevance.  Another
technique used is the dialogue of the young couple in love.  The scorn with which they
deride Miss Brill is the first moment in which she is shown to be a part of this world,
and that function is an isolated or relegated one.  The theme of the outsider is evident
at that point.  I would say that the ending is another instance in which it is clear
that Miss Brill is an outsider.  She is not shown to be who fully understands the
implications of being on the outside look in, meaning that it is likely to continue. 
The fact that Miss Brill blames the fur stole for what the couple said indicates that
she is not fully cognizant of her outsider status and this tells the reader that it is
not very likely to change as a result of this lack of comprehension.  These techniques
advance the theme of alienation and the condition of being an outsider in a specific
social setting.