No contact order with child visitation involved? What is the right thing to do?

For the visitation, the order still stands and she should still have her visits unless the court order is modified. You as a step-parent can be utilized in place of the father for exchanging the child with his mother. Since she does not want you at her house, a neutral place (like a park, McDonalds....) can be agreed upon for exchanges to take place at the times according to the schedule. Remember however, that you cannot force the mother to come visit with her child and if she refuses come get him at the appropriate time and place, then that visitation period is missed.