Gracey please have a plan e (for escape) in place just in case and also a phone - land line or cell that you can use to call for help if it's needed.
I know it's a tough choice between doing something you have every right to say No to and having it turn into a marathon verbal torture session. In the end, you have to do what is right for you. Talking to a lawyer and knowing your options will really help.
SusanD is very very right, they do get worse as you try to leave/escape - a control issue. You've already experienced his meaness torwards your older daughter. Many times they try to hurt the children mentally or physically to get to you.
Whatever you do, please put your safety and your children's first.
My prayers are with you.