I don't know what book that is but based purely off the excerpt, I assume that Edna is beginning to realize that she wants to be more independent and to isolate herself. She wants to make decisions for herself.
Hope that helped! Again I haven't even heard of that book so sorry if it's not 100%!
A diamante poem is a poem that makes the shape of a diamond. Thepoem can be used in two ways, either comparing and contrasting two different subjects, or naming synonyms at the beginning of thepoem and then antonyms for the second half for a subject.