How do you want to do it?

I suggest #1 put your attention on D16 and her and her group's performance. Immerse yourself in it and enjoy it. Celebrate her achievement.

The OW does not deserve your attention.

If she inserts herself into your attention:

"OW, I am here to enjoy my daughter's performance. I don't speak to people that mistreat me and my family. I hope you enjoy your niece's performance."

And turn away.

Me-53
W-49
D22,D18,D15
T-Since-12/2001
Married-9/2004
She Moved Out-5/28/2010
Piecing start-04/2011
Now-together
Thread
http://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2079304