I would address it, just stating the facts, without any emotion and judgment. I would say sorry that it had to be this way. I think it is better if they know your side of the story. It is up to them to believe it or not, but I bet I will make you feel better.
M:50 H:52 S28 (my S from previous marriage) M:17 + 3 BD: 06/12 S: 06/12 - H works in another state