How plausible do you find Cathy's relationship with Hareton?

Cathy had a bad relationship with Hareton but finally relents and softens to him. Hareton, although skeptical, softens to Cathy as well. I think the main obstacle they overcome is Hareton's insistence that Heathcliff be respected by Cathy. In the end the cousins do find a way to strengthen their relationship. In chapter 32 Nelly relates a scene where the two are huddled over a book in a sort of domestic bliss.

"Intimacy thus commenced grew rapidly...both minds tending to the same point one loving and desiring to esteem, and the other loving and desiring to be esteemed, they contrived in the end to reach it".