I would take not being introduced to his family as a very bad sign . . .I don't introduce everyone I date to my family but after two years.
It seems to me that you need to ask him what's up - its possible if the relationship ended poorly that his family has a negative opinion and he's not sure how to tell them that he's back with the girl that broke his heart before. It's also possible that he thinks you aren't interested in meetings his family. Only one person knows for sure what's going on in his head - and that's him.
It could also be that he doesn't want his family pestering him about settling down!
I think the mistake a lot of us make is thinking the state-appointed shrink is our friend. - Jack Handy