David pauses his narration, overcome by memories of his "child-wife" Dora, whom he imagines begging him to "stop to think of [her]." He imagines himself back with her, explaining that he has lost track of how long she has been ill, but that it is slowly becoming clear she will never recover. Jip, meanwhile, is old and frail, and spends his days lying next to Dora. However, Dora is uncomplaining and grateful for the time David and Miss Betsey spend tending to and talking with her. Sometimes Miss Clarissa and Miss Lavinia visit, and everyone reminisces about Dora's wedding. David explains that he felt as though everything in his life was on pause during this period, but that a few incidents do stick out in his mind.
Even as a narrative device, the image of Dora asking David not to skim past her is striking. On the face of it, there doesn't seem to be much danger of this; David clearly remembers Dora fondly and takes pleasure in recounting her story. However, in the context of the novel as a whole, David's marriage to Dora functions mostly as a learning experience—specifically, one that teaches him what he ought to look for in a wife. It's interesting, then, that David "stops to think" of Dora—that is, pauses the forward momentum of the narrative to describe her death. Perhaps in doing so, David is trying to recall Dora on her own terms rather than as a precursor to Agnes.
One morning, Dora shows off her curled hair to David, saying that she often thinks about how much he liked it when they were courting, and how she eventually gave him a lock of it. David reminds her that it was the same day she painted the flowers he brought her for her birthday, and the day he confessed his love for her. Dora replies that she used to cry over the flowers David gave her, because she was so happy to think he liked her. She then suggests going to visit some of the places they used to go. David says they will when she is better, and Dora insists that she is "so much better" already.
Tellingly, Dora's happiest memories seem to be of courtship rather than of marriage. As she draws closer to death, she seems to spend more and more time reliving these early days with David, when her childishness and innocence weren't liabilities.
On another day, David is sitting next to Dora's bedside, since she no longer leaves her room at all. She asks him whether it would be alright for her to ask Agnes to visit, given Mr. Wickfield's condition. David assures her that he will write, and Dora thanks him, saying that it isn't simply a "foolish fancy" on her part. She then asks whether David is lonely downstairs without her and—when he says that he is—starts to cry, saying she is both sorry and glad. Finally, she reiterates that she wants to see Agnes more than anything. David reminds her that her first wish should be to get well. To David's distress, Dora confesses that she doesn't think she will ever be healthy again.
Towards the end of the novel, Agnes admits that Dora gave her permission to marry David after her own death. Narratively, this seems intended to ease any concerns readers have over David's behavior towards Dora both before and after her death, and the smooth transition from one marriage to the next begins here, with Agnes arriving in the household as Dora is dying.
One night, David is sitting alone with Dora. Agnes and Miss Betsey are present, but downstairs. Although David is aware on some level that Dora is dying, he still does not quite believe it. Dora interrupts his thoughts, saying she needs to tell him something she has been thinking about for some time, although she isn't sure how he will react. David lays his head on the pillow beside her as Dora confesses that she thinks she "was too young" and naïve when they married, and that it might have been better if they had had their youthful romance and then moved on. David protests that he was not ready to marry either, but Dora says that she might have made him readier if she had been more mature. Furthermore, she says, David was too "clever" for her.
The fact that it is ultimately Dora who explicitly suggests that she and David shouldn't have married is another way in which the novel tries to cast David's actions in the best possible light; David senses vaguely that Dora isn't the best match for him, but he never goes so far as to say that he regrets marrying her, which might make him less sympathetic to readers. What Dora says, however, is clearly the position of the novel as a whole—that is, that David and Dora's relationship was based on an immature understanding of love and marriage, and that Dora in particular couldn't have fulfilled her duties as a wife. In other words, Dora's deathbed confession allows Dickens to underscore an idea central to the novel without calling David's character into question.
David insists that he and Dora have been very happy, and Dora says that this is true, but that David would likely have tired of her as time went on. David, in agony, says that everything she is saying is a "reproach," and Dora insists that it is not, because she loves him too much to scold him. She then asks again if it is lonely downstairs, and then says she wants to speak to Agnes in private. David promises to fetch her, and Dora once more repeats that it is better for her to die now.
Dora's calm acceptance of her death, like her earlier admission, is a way of downplaying anything that seems questionable about David's treatment of Dora. With that said, Dora's remark that David would eventually have regretted marrying her clearly disturbs him, probably because he realizes it's true and feels guilty.
David waits downstairs as Agnes goes to speak with Dora, watching as Jip sleeps uneasily in his dog house. Weeping, he begins to think back over his dissatisfaction with Dora, as well as over their courtship, and he wonders whether Dora was right to say they should never have married. Eventually, Jip crawls out of the dog house and indicates that he wants to go upstairs. David tells him that he can't tonight, and Jip crosses over to David, licks his hand, and lies down and dies. David cries out for Agnes, and, realizing from her expression that Dora has also died, falls into a stupor.
Dora's words stir up the "secret feelings" David has "nourished" throughout his marriage. Although the "remorse" he feels while thinking back on these feelings (and the relationship as a whole) suggests that he recognizes that Dora is right, but he doesn't explicitly say so in this passage. Again, this serves to minimize David's culpability in the eyes of readers. Meanwhile, both Agnes and Jip play pivotal roles in this scene, with Jip's death underscoring his similarities to Dora, and Agnes immediately assuming the position of caretaker to David, which Dora has now vacated.