Becky is actually quite moved by Amelia's PDA. She feels sort of bad about having to pretend that she's tormented about Rawdon Jr., but there's no way around it now.
Amelia immediately falls for Becky's version of the events surrounding her marriage and separation, especially since Becky is clever enough not to speak with anger about Rawdon, but only wistfulness.
Meanwhile Dobbin is hanging out downstairs in the hotel and overhears two students talking about Becky. Their conversation makes it clear that she is planning on putting on a concert of some sort (and selling tickets), and that she likes to have a drink or two (or three).
Dobbin reminisces about the old days then remembers how George half-confessed wanting to have an affair with Becky two months into his marriage. (Though his memories reveal that George never actually told Dobbin how far along he had carried his plan out.)
In any case, he is as much against Becky as ever.
Amelia comes back to Jos and the two of them decide to let Becky stay at their house.
Dobbin is totally outraged. He huffs and puffs, then makes an ill-timed allusion to Becky's behavior with George.
Now it's Amelia's turn to be outraged. She basically kicks Dobbin out of the house and all the bits of love she had been kind of feeling towards him seem to dissipate.
Man, that guy just never gets a break!
Just as he's leaving, Becky arrives with her few belongings. She tells them that most of her luggage is still in a different city, waiting to be forwarded. (Um, yeah, not so much.)
They have dinner without Dobbin, and George Jr. wonders where he is.
Afterwards George Jr. recognizes Becky as the woman he met at the gambling rooms, and she tells him not to tell anyone. He agrees.
The same night, Dobbin goes to dinner with Tapeworm, the British ambassador. This guy knows everything about everyone, and he tells Dobbin the real deal about Becky, Steyne, and the whole sad mess.
Poor, innocent Dobbin is beyond shocked.
The next morning he goes over to Amelia and Jos's house. He wants to talk them out of letting Becky stay there, but when he walks in, Becky is with Amelia. Amelia is still pretty angry, and she pulls the old "anything you say to me can be said in front of my friend" thing.
Which is fine to say, but not actually true, of course. Dobbin is a real gentleman and can't repeat the things Tapeworm said to him with Becky there.
He tries to say she's no good, but Becky is a much better talker and she lawyers around his arguments.
Amelia isn't having any of this anyway, and she tells him she will never forgive him for making a reference to George's near-affair.
Dobbin is totally crushed by the situation.
He asks to have a word alone with Amelia and tells her it's over. He has loved her forever, and she isn't really worth the sacrifice. He tells her he is going away again.
She is all, "What?"
Which is to say that maybe she does actually have feelings for him after all.... Oh, the drama! But seriously, she really isn't worth it, is she?
At dinner that night, George Jr. sees Dobbin's carriage being set up and freaks out when Amelia tells him Dobbin is going on a long trip and never coming back.
George Jr. runs into the street, hugs Dobbin good-bye, and then stands in the middle of the road crying as Dobbin drives away. Awww. He loves his almost-stepdad.