Toast - burnt or just right

[CWOL]

My WW tried to shore herself up after she learned I told S11. She brought the three of us together, and wanted to explain that we decided to split up, but I interrupted her and told S11 remember, it is WW's decision alone, I was more than willing to work things out with WW as long as she cut OM out of our lives. She got livid of course. I was not going to have any of the "we decided together..." BS. I wanted my S11 to know what is right and what is wrong, and he got the message very clearly.
In the end, no amount of explaining by WW can overcome the true facts, and I feel that was very important in my situation.
Your situation is probably very different due to your D's age, but I wouldn't dance around the facts too much. Children have a way of figuring things out, and you don't want them to get a warped distortion of reality.