Although, as boys, we had been even intimate associates, yet I really knew little of my friend. His reserve had been always excessive and habitual. (3)
And even as the narrator gets to know Roderick again, there remains a barrier between them. Roderick remains excessively reserved.
I had learned, too, the very remarkable fact, that the stem of the Usher race, all time-honoured as it was, had put forth, at no period, any enduring branch; in other words, that the entire family lay in the direct line of descent, and had always, with very trifling and very temporary variation, so lain. (3)
The Usher family was as self-isolating and insular as Madeline and Roderick seem to be. Insular means lacking contact with other people.
The windows were long, narrow, and pointed, and at so vast a distance from the black oaken floor as to be altogether inaccessible from within. (7)
There is a definite sense of confinement here; the windows are out of reach, to escape is impossible.
He was enchained by certain superstitious impressions in regard to the dwelling which he tenanted, and whence, for many years, he had never ventured forth. (12)
Poe reiterates the Ushers’ isolation, and strengthens the connection between Roderick and his mansion.
I learned that the glimpse I had obtained of her person would thus probably be the last I should obtain--that the lady, at least while living, would be seen by me no more. (14)
Madeline, like her brother, responds to her illness by isolating herself to the greatest possible degree.
A small picture presented the interior of an immensely long and rectangular vault or tunnel, with low walls, smooth, white, and without interruption or device. (17)
Sounds a lot like the tomb that will eventually enclose Madeline…here, then, is another case of Roderick’s prophetic sight.
A striking similitude between the brother and sister now first arrested my attention; and Usher, divining, perhaps, my thoughts, murmured out some few words from which I learned that the deceased and himself had been twins, and that sympathies of a scarcely intelligible nature had always existed between them. (24)
The narrator’s role as an outsider to a very closed-in world is made evident in this passage.