Im not going to say that what i did was right, but i just ignore the existence of ow. I have no interest in getting acquainted with my H secretary, as that is what she is at work. And if it ever came uo thats exactly what i would say. I have high standards and im a bit picky about people i let into my life.
When it comes to kids, honestly mine still think that they are friends and that ow is not an obstacle for H to come Home, they are still hopeful. They occasionally mention her, often funny or not so situations. Like H telling her off for something, but she is very much irrelevant in their lives, just there.
If i was you, i wouldnt ask anything. Just crack on with your life, if the questions come just be honest. I just say to mine that H wants to live with her and thats how it is and yes its really sad for them that we are no longer a family. Thats it.