How we cite our quotes:
Of course it was not only childish defiance and the self-confidence she had recently acquired so unexpectedly and at such a cost that led her to make this demand; she had in fact noticed that Gregor needed plenty of room to crawl around in; and on the other hand, as best she could tell, he never used the furniture at all. (2.22)
Even though Gregor can no longer support the family financially, the family's condition actually seems to improve. In this passage, Grete becomes more independent and assertive by taking on the responsibility of caring for Gregor.
Sometimes he thought that the next time the door opened he would take charge of the family's affairs again, just as he had done in the old days […] At other times he was in no mood to worry about his family, he was completely filled with rage at his miserable treatment, and although he could not imagine anything that would pique his appetite, he still made plans for getting into the pantry to take what was coming to him (3.7)
This passage suggests that Gregor's transformation isn't just a physical one, but operating at a level that he himself is barely conscious of. Gregor seems to be in touch with his pre-vermin life, the responsible Gregor who supported the family and directed household affairs. But the insect side of him, that just wants to stuff his face regardless of what the others think, is just as much a part of his consciousness. If it is the insect side of him, that is – we have no way of knowing whether he was like this before.
At first he thought that his grief at the state of his room kept him off food, but it was the very changes in his room to which he quickly became adjusted. (3.9)
As the passage suggests, Gregor's transformation didn't end when he woke up in his bed as a vermin, but continues as his environment changes. In contrast to Part 2, where he resisted the changes to his room because he associated the furniture with his human life, in Part 3 Gregor accepts the changes, which suggests that he accepts his insect body as a permanent fact of life.