What is it Mary Shelley sees? The plural suggests that the antecedent is "realities."
But the realities she remarks are those of Victor's bedchamber as well as her own.
Like hers it is described as barely illuminated "by the dim and yellow light of the
moon, as it forced its way through the window-shutters" (see I:4:3). As in the previous
paragraph, the novelist seems deliberately to conflate her experiences with those
of her fictional protagonist.