I totally understand your feelings on this. The idea of a woman I did not choose driving my kids around is a bit unsettling. Just as the idea of my child going on a vacation without me there makes me feel sick. Some times I get so upset and then realize later, I overreacted. Maybe you will find later, you're ok with it. If your ex had asked first, it might not seem so terrrible. Maybe speak with your ex and let him know you'd appreciate a heads up.

Mandy, your ex-husband is emotionally abusing you and your child. You need to file a Domestic Violence Restraining Order. You can file against current and former husbands. You have no idea how female-friendly the domestic violence laws are. Tell the truth. Some woman is driving around your child. You are afraid for your child's safety. The woman drives in an unsafe manner and is endangering your child. As long as you say your husband is using this other woman to harass you, you can ruin his life and put him in his place. You need to file a Restraining Order immediately. If you can bait him into meeting with you, get him to have a verbal argument, then saying he hit you or you felt like he was about to hit you, even better. As part of the Restraining Order, the Judge will prevent child visitation if you ask for it. Good luck.