Besides Estella serving as the key motivating factor for Pip's wanting to become a gentleman (he thinks that this will win him Estella's love and respect), Dickens uses her character to tie together almost all of the novel's subplots. She is Magwitch's daughter, and he is Pip's benefactor (ironic since Pip believes that Estella's adopted mother is his benefactress). She is the daughter of Jaggers' mysterious servant Molly. She eventually marries Pip's arch rival Drummle, and of course, her ties to Miss Havisham initiate the book's main plot (Pip's maturation process).
Often cited as Dickens’s first convincing female character, Estella is a supremely ironic creation, one who darkly undermines the notion of romantic love and serves as a bitter criticism against the class system in which she is mired. Raised from the age of three by Miss Havisham to torment men and “break their hearts,” Estella wins Pip’s deepest love by practicing deliberate cruelty. Unlike the warm, winsome, kind heroine of a traditional love story, Estella is cold, cynical, and manipulative. Though she represents Pip’s first longed-for ideal of life among the upper classes, Estella is actually even lower-born than Pip; as Pip learns near the end of the novel, she is the daughter of Magwitch, the coarse convict, and thus springs from the very lowest level of society.
Dickens uses Estella’s life to reinforce the idea that one’s happiness and well-being are not deeply connected to one’s social position. He argues that had Estella been poor, she might have been substantially better off.
Estella’s long, painful marriage to Drummle causes her to develop along the same lines as Pip. She too learns, through experience, to rely on and trust her inner feelings. In the final scene of the novel, she has become her own woman.