Fairly horrible, I should think. That's because Elly won't allow herself to feel gratitude.
Panel 1: We start off with Elly making the Bug-Eyed Glare of Confusion because she sees John cleaning the floors; she cannot (and will not) believe what she's seeing.
Panel 2: He explains that the floor was dirty so he decided to wash it.
Panel 3: She points out that they've always been honest (yeah, RIGHT, Repressa of Sunnyfoob Farm!!) with each other...
Panel 4: ...so he should have no problem telling her if he's simply currying favor or trying to make her feel guilty. This is, of course, because he cannot simply clean the floor. Either he wants something from her or he's trying to make her feel inadequate.
Summary: Elly's distrustful, negative nature has once again made everyone;s life worse. Not only can she not feel the least bit of gratitude for help around the house, she's slowly but surely making sure that no one is willing to risk doing so.