Alas! Madame St. Aubert knew not that she left it forever. (1.1.26)
Hold up. So the narrator's gonna throw a major spoiler in there like it's no biggie? It just goes to show that death's pretty abrupt in this book.
St. Aubert lifted up his eyes; the spirit of a father returned to them, but it quickly vanished, and he spoke no more. (1.12.27)
When Em witnesses her dad's death, it shakes her to the core. She'll always remember the moment she saw his spirit disappear. Pretty traumatic, we think.
She was recalled from her reverie to a mere mortal supper, and could not forbear smiling at the fancies she had been indulging […]. (2.2.28)
All this time, we've been thinking that Emily is obsessed with her own mortality. But what if it's the other way around, and she sees herself as being this otherworldly creature?
How happened it, that her remains were never found? (2.7.107)
The absence of Signora Laurentini's body opens up a whole bunch of speculations about the living and dead. Is her spirit at rest?
"Not till you speak reasonably, Annette; for Heaven's sake, explain your meaning. You spoke of murder!" (2.9.12)
Annette may be silly, but she prompts Em to think of mortality in a different way. In Annette's world, it's all about murder and the macabre.
"For Annette," said he, "if you go to Carlo, he will release the girl; the foolish fellow, who shut her up, died yesterday." Emily shuddered. (2.11.7)
For a totally opposite view of death and dying, check out Montoni. Death is so commonplace for him that he doesn't even consider the impact of his words.
"She is dead!" she cried—"murdered! —her blood is on the stairs!" (2.11.68)
Granted, Em's just stumbled across a dead body. Her reaction is actually totally warranted, though she might consider that the "murderer" is still lurking around. It's one of those moments where you can't help but yell at her.
"For since my father died," added she, sighing, "everybody forsakes me." (3.1.34)
Ah, now we get down to the nitty-gritty stuff. Em associates death with the worst kind of abandonment.
Emily, shuddering with emotions of horror and grief, assisted by Annette, prepared the corpse for interment. (3.5.3)
Preparing a body for burial is a pretty traumatic event for a young girl to go through. Emily is getting a trial by fire.
"Ah! Dear young lady! is death not always terrible?" replied Dorothée. (3.12.25)
At this point, Em's been exposed to so much that the mere act of dying isn't a terrible thing. All the ghosties and ghouls are what she's really worried about.