Can I just leave my home and come back to get my child back

Leaving your house may affect your ability to get custody in the future.  Even if you leave the house, you must make sure that you stay in touch with your son, regularly visit, stay active in his life and be sure that he knows how to get in touch with you at all times.  You do not want a claim that you "abandoned" him or that you are and unfit mother.  You may also be able to do a pro se (without a lawyer) application to decide custody and/or visitation before you leave, or just after you leave.  The New Jersey Judiciary website has pro se packets available on line.  Scroll all the way to the bottom and look through the paperwork and see if there is something that you can file before you file for divorce that wold give you support, and custody.  Its called pendente lite relief.  Good luck.