With modern high divorce rates, a lot of people get married more than once in their lives. Saying "my ex-wife's new husband" is a bit awkward. Is there anything more graceful?
I came across it in this video: http://www.youtube.com/watch?v=RqXGxLWPWMQ. They proposed "ex-in-law" and "outlaw", mostly in jest.
Best Answer
No, there isn't.
This sort of kinship relation is relatively new to Anglophone cultures, and there are really no established norms to follow. It takes centuries for terms like this to populate the language and its culture.
Really, you have two options -- or more correctly, a mix of the two:
Counterpartner is a reasonable and logical relational term, which unfortunately means that nobody's ever heard of it, and likely won't understand it.
But maybe it'll make them ask, if that's what you want.