While you "sit tight" be good to yourself...go nice places and keep busy..it will sustain you until the time is right to discuss the future.And act if necessary
Your son wil be between a rock and a hard place so he will be going through a serious time.
I feel sure if the mother does something wrong A. will tell Daddy..watch out if she isnt telling but seems unhappy....he must act and sadly you two must wait.
So....where are you going today ? an art gallery ? a coffee shop ?