I know your resources are limited, but what you really need is an expert on domestic violence and parenting. Lundy Bancroft, who wrote "Why Does He DO That?" has written a book for legal professionals called, "The Batterer As Parent," which describes all the things that abusive men do that are along the lines of what you are experiencing.
I would suggest contacting your local domestic violence agency and talking to them. It could be that they know of someone who would be able to take your case for a reduced fee--maybe a therapist who treats batterers in a batterer's intervention program, or someone else well-trained and experienced in the field.
I'm so sorry you are dealing with this.