apparently this term is used to describe women who are dumped by their husband for a younger woman. i have seen ads for a movie titled "the starter wife" on the usa network. i looked it up online to investigate and on their site they have stories from women who consider themselves "real life" starter wives. i have to say, the stories have how these women moved on is very inspirational.
http://www.usanetwork.com/series/starterwife/sexyandsassy/
http://www.usanetwork.com/series/starterwife/sexyandsassy/