DW,
In NJ you will get support for your children. You also can get spousal support (maintance) for you. Have your lawyer file a motion ASAP for this. Make a list of all your bills, and I mean everything you pay, and give it to your lawyer.
Open an Account with just your name on it, and take as much as you can from the joint account and put into yours, (all is not to much) this way you have money to pay bills. If you leave it in there no one knows how much you will have left tomorrow, or next week. If you can get to the bank today please do it.
You can not change the cell phone unless he does it, I know with verizon only the person who is listed on the account can change it. If you can open your own account for a cell and get the cheapest plan you can.
I am praying that things go well for you. I am here if you need me.
Hugs and prayers coming your way