Have you completed a program or been to a prgram to help you with your addiction? Most of these places have social workers that can help you.
Was you suppose to complete a program and/or parenting class by a social service. You have to have a social worker so it is best that you talk to him or her to find out what you can do because most likely you would've to go back to court and prove that your capable of thinking care of your kids.
Also, seeing a counselor might help you too because that can at least help to prove that your mentally able to deal with your kids.