You could file for divorce. Once you file, if you and your wife cannot agree on custody, child support and parenting time, the court would determine each of your rights. Based on the facts presented, you could ask the court for supervised parenting time only and for full legal and physical custody. Once there is a court order, both of you would have to follow it (except you could not force her to use her parenting time) and it would prevent her from just coming over and picking up the kids.
Answered on Jan 30th, 2013 at 12:19 AM