Hi D.,
First of all, best of luck to you. I know this is hard...I am going through it myself. You can put a right of 1st refusal in your decree. Typically, it is applied when your x can't be with the kids for a minimum of 24 hours. In my case, I changed it to 4 hours. We are both living with our parents while the divorce is pending and I do not agree with his mother's parenting approach, even though my x is a great father. My intent was to prevent him from having his mother raise our children. He has agreed to the 4 hour change, but keep in mind, it goes both ways. Good luck and stay strong! There are good days and there are bad days, but as time goes on, there will be more good than bad.
L.