Answer:
Roderick Usher is not well. While parts of his affliction seem to manifest themselves physically, in his overly-acute senses, his illness is primarily a mental one. While his sister is cataleptic and wasting away, Roderick is tormented by, to be quite honest, his own fear. By his own admission, he doesn’t so much fear any particular thing as he fears his own fear. And one day, he predicts, this affliction will kill him.
Which it does, pretty much. One conclusion to be drawn from the final scene is that Roderick dies of fear. Madeline rushes upon him and he falls to the floor a corpse, too terrified to go on living. As we’ll talk about in Madeline’s “Character Analysis,” it’s even possible that Madeline is just a physical embodiment of Roderick’s fears.
Credits to: thompcd
Not mine!