How we cite our quotes: (Section.Line)
Quote #1
Yet the moth has trim, and feistiness, and not a drop
of self-pity. (4.7-8)
Our speaker hasn't directly addressed the idea of sadness yet, but we get a glimpse of her feelings on the matter here. She clearly admires the moth, in part because it doesn't have the slightest bit of self-pity. Since the lack of self-pity goes along with lively attributes like "trim" and "feistiness," there's the suggestion that self-pity goes along with a certain dullness or un-liveliness.
Quote #2
my mother, alas, alas,
did not always love her life,
heavier than iron it was
as she carried it in her arms, from room to room (5.5-8)
This image is really powerful and shows us the weight of sadness as our speaker sees it. Her mother is an example of how not to live one's life. Iron is pretty heavy, so if her mother's sadness made her life heavier than iron, well, that's pretty sad.