While the family is waiting for her to pass on, she herself is waiting for "...the King..." (li 7). No, we're not talking about Elvis, but instead this King is some sort of omnipotent being, a god. Later as the woman dies, her eyes (or windows as they are referred to in the poem) fail, then she "...could not see to see-" (li 16). When she says this, what she seems to mean is she could not see any of the afterlife or Kings she expected to be there. The woman's soul drifted off into nothingness with no afterlife to travel to.
To conclude, the beliefs of the two Dickinson poems in regards to life after death differ significantly. In one, "Because I Could not Stop for Death," the afterlife does exist, in the other, "I Heard a Fly Buzz- When I Died," it does not. It seems that Dickinson, too, questioned the question of whether or not there is an afterlife, and she herself, being so in touch with death, could not come to a solid conclusion. There is only one way to tell.
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