How does Pip change after he meets Estella in Great Expectations by Charles Dickens?

In the First Stage of Great
Expectations by Charles Dickens, young Pip is content with his life on the
forge.  Fond of Joe, Pip revels in the sunshine of his love and protection from the
wrath of his sister.  However, once Pip goes to Satis House to play with Estella, his
world assumes a different appearance for Pip.  Ridiculed for being "a common laboring
boy" who has coarse hands and boots, Pip returns home with a new perspective.  For, he
is now class conscious and feels inferior.

Pip subsequently
begins to envy Estella and desires to beome a gentleman so that she will no longer
ridicule him. After he is apprenticed to Joe, he is disconsolate and ashamed of his
lowly position whereas before he went to Miss Havisham's he looked forward to the day he
could work with Joe.  Now, he worries that Estella may see him as this apprentice and
scoff at him. 

When Mr. Jaggers arrives to tell Pip about
his "great expectations," Pip is elated and hurries to London and his new life as a
gentleman.  Once in London, Pip has his roommate Herbert Pocket teach him table manners
so that he will know what to do if he dines with Estella.  In fact, everything that Pip
does is enacted with Estella in mind.  When Joe comes to visit him in London, Pip is
embarrassed by him in front of Herbert because Joe is so uncomfortable in the
apartment.  Joe apologizes as he departs and tells Pip that he will come no more because
he "belongs on the forge." 

If Pip does see Estella, she
simply uses him to escort her or pick her up when she arrives in London.  Estella is
cold towards Pip and is often escorted by the brutish Bentley Drummle, who, of course,
becomes Pip's rival in his mind.  So consumed is Pip with his love for the unattainable
Estella that he neglects the loving Joe at the forge.  And, while Pip does recriminate
himself for not visiting, he has become so snobbish that he stays at the Blue Boar Inn
instead of going to his old home.

It is not until Pip is
burned and the solicitous and loving Joe cares for him that the shamed Pip apologizes. 
Later, too, he begs Biddy to forgive him for his snobbery and remarks which he made
about her not improving Joe enough. Like the prodigal son, Pip has returned to the forge
because all his attentions to Estella have been for nought as she cold- heartedly
marries Bentley Drummle.  It is not until much later in their lives that Pip and Estella
reencounter each other, and both have been changed by suffering.