About SVT's comment-

If Terry had changed him so much then why would he just up and go so quickly back "home" ?

It may have seemed as though Terry was going to be an extremely positive influence on his person, but for a man who is known for his spontanaeity she may have been expecting too much. Terry was too good and the plot was slowing, so something had to happen to make them split and regain the readers attention. Granted, the trip home wasnt nearly as eventful, and his dialogue with the aunt is a tad more mundane than getting drunk every night..well, i guess we'll just see..