Thanks labug - this really is food for thought.

I'm having a real struggle trying to accept that OW has any right to show up at my kids' school functions.

I know this is eating me up, but I just can't seem to get my head around it. I accept that I have no control over what she does - but I can't take the next step at the moment and think - ok, I will just ignore her.

I see my kids hurting and i just think she needs to know how much pain she has caused. If she's gonna turn up, she should take the heat, as it were.

She was preening and mugging and talking over other kids' performances on Monday, and even screamed out a very inappropriate "Woo Hoo" at the end of her niece's piece. Made me so angry to see her flaunting herself at the concert - she didn't even have the decency to sit quietly...
Here i go again!

I know I'll have to get around this, but I'm still struggling.

Thanks for your detailed suggestions about how to move on, it really helps and gives me hope that i will get there soon.