I am reading The Great Gatsby, and encountered these sentences:
The voice begged again to go.
"Please, Tom! I can't stand this any more."
Her frightened eyes told that whatever intentions, whatever courage she had had, were definitely gone.
"You two start on home, Daisy," said Tom. "In Mr. Gatsby's car."
She looked at Tom, alarmed now, but he insisted with magnanimous scorn.
"Go on. He won't annoy you. I think he realizes that his presumptuous little flirtation is over."
They were gone, without a word, snapped out, made accidental, isolated, like ghosts, even from our pity.
In this part, Daisy, her husband Tom, her lover Gatsby, her relative Nick, her friend Jordan came to the suite parlor in the Plaza Hotel to have some cold drink on the stifling day. The room became the battlefield between her husband and her lover, when each began to claim that it was him that Daisy loved. Tom had made some small "investigation" regarding Gatsby's past, and revealed the information during the argument that he earned his money through not very honorable routes. At this astounding information, Daisy felt her love toward Gatsby fail. Seeing the two already crumbling, Tom generously allowed Gatsby to drive her home.
I find the last sentence especially difficult to understand. How could they have been "snapped out"? And I could not grasp what "accidental" means here either—does it mean that their encounter was reduced to a merely accidental one, not a destined one? And what does it indicate that they have become "isolated" and "like ghosts"?
I would very much appreciate your help.