Oh busting, I was thinking something similar to what Ruby said.
I did that for too long, put my self in the range of hurt. I know with younger children it's more difficult but you need to save yourself.
You're putting a lot of meaning on things without knowing the truth and causing yourself pain. He's missing her production-I can see being a bit pissed about, so acknowledge and move on. Spin his choices to neutral when you can. Don't try to figure out why he's doing it but the reason is probably quite basic-he's having illicit sex with a woman he sees only occasionally and who he has no emotional baggage with (yet).
Don't be the person who life does things to, be Busting who creates her own life!
But it's really between him and his daughter. They will have to figure that out down the road.
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss