Foolish as it might be, Rey truly does want to believe that Bianca will hold true to her word. That perhaps Rey can help her strive to be a better person. Ironic, really, considering that she doesn't view herself as a very good person in the first place, regardless of Nick's impressions of her. Arguing that notion is a fruitless endeavor, though.

Her face gets hot at his offer, and it's probably a good thing that she can't see her own reddening complexion just then.

"What is there to even talk about?" It isn't like Rey has ever had to discuss relationships with anyone in depth before.