Never give up on your kids. Always let them know, even if it feels like you are losing a particular fight, how much you love them. Keep fighting all the ugliness of these situations with that one recurrent theme: you love them, you love them, you love them.
I am still fighting for the hearts and minds of some of my kids after nearly 3 years. It is a fight I will never surrender. This doesn't mean I will necessarily win or win in the way I want...but I will not give up.
