First – Chill – then Stupor – then the letting go –
This line represents the transition, once again, from agony to numbness, represented by the change that people physically undergo when exposed to cold. First comes the chill, which is extreme pain. Stupor is unresponsiveness. Letting go, then, can represent two things, either death or acceptance.
Death can represent the idea that the narrator is overcome by extreme pain and sadness permanently and “dies” as one would of hypothermia. However, “letting go” can also refer to letting go of the pain, and that death is some kind of permanent relief from suffering, perhaps symbolizing acceptance or coming to terms with what happened.
In a way, this line can represent the choice of the narrator, either to drown in terrible event and its memory, or to somehow regain her humanness, through letting go of the pain associated with the memory in order to heal. The rest of the poem makes it seem likely that Dickinson thinks a negative outcome is more probable. She probably expects that the narrator will lose herself or die from the pain.
(credit to: http://noahhutchison.com/)
Dickinson might disagree.
To help improve the meaning of these lyrics, visit "After great pain a formal feeling comes (J341, F372)" by Emily Dickinson and leave a comment on the lyrics box