Trying to find a story from way back. As far as I can rememeber it is about a middle aged man (widowed) who is touring the USA in a converted bus/coach. Early on he picks up a college aged girl and they continue the road trip.
Beyond that the memorys are a bit sketchy other than...
1. There is a sex scene in the last carriage of a tourist train.
2. His family (or maybe it was his wife's) are actually a brother and sister living together.
3. They eventually settle down and buy a house and she goes back to college to become some kind of architect/engineer.
Have racked my brain for a title or author but can't remember (or find) either.
A.