The narrator's opinion is captured in a metaphor:
- "She was a master of the art of graphic description"—he's comparing her to a performer, and emphasising her mastery.
He expands with some detail, then reinforces the description with a related metaphor:
- "She would give us such a realistic picture of her suffering"—he's again comparing her to an artist, this time commenting on her realism.
After which he expands with more detail.
Overall, the narrator sees this annoying behaviour as a masterful performance, something worthy of a kind of respect and admiration because it was so over the top and affecting.
(Note how this tells us something about the narrator as well as his neighbour.)