You've hit the nail on the proverbial head. She is NOT interested in his "lower class" family (especially since they haven't bent over backwards to honor her when she deigns to grace them with her presence), and would prefer it if he would forsake them for the "new and better" family he would have with her. I would say it's not a good match.

I have a family member (now an ex family member) that always put HER family before ours. Most holidays and occasions did not include them because HER family came first .... period. They are divorced now.