What can I do to get help with my kids my wife left me and the kids for a month and she wrote out?

well my wife left me the boys and wrote out that she gives full custody to the father shaun d hall me and her own family was the wittnesses on it when it got notirized she gave them permission to and a month later she showed up and took them with a cop and the cop came and told me he was sorry he had no right to get n it but now she is with this 30 year old drunk named rob and my five year old told me that he watched him a girl record themselves having and *** to find out it was his mom and he told me and I asked her and she saide he lieier and started maken him lie to me cause i said i didnt want him round my boys then he told me the truth and said I wanna live with you all his mom does is drink pop pills and trade the boys foodstamps 100 on pills and drugs she has pipes and pills layen round her house and i called my son today and she yanked the phone out his hand and told me to never call them again and to stay out there lives they got a dad now and she put a xpartie on me and adult abuse when I aint seen her n a long time I wanna see my boys for easter they want to live with me and I want them to had them since born she always pilled out and sleeping or screaming at them and I cant afford a lawyer she took everything so if could help would really appreciate it with greatness