Nothing. If you do anything you are the bad guy. Be supportive and friendly and don't say anything unless asked.
I'm a women, an I recently found out that my, now ex, is bi sexual, and had been lying to be about it our entire relationship up until a couple weeks ago. We were together almost 2 years, and very close to being engaged. What would you do?
Be thankful that he is now my "ex."
He is ex, what seems to be the problem now? You worried you didn't swing both ways?