Keep my Children Safe

My names Odessa I am a mother of 3 young children. A 6 year old boy, 5 year old girl and a 5 months old boy. 5 months ago my life flipped upside down. A month prior to that i was hospitalized for 28 days due to complications with my pregnancy, 23 days in i was induced at 36 weeks for the safety of me and my baby. After the birth he was healthy but i was not. I had 2 procedures done to control bleeding. And i almost lost my life. When i was finally discharged 4 days after i got home. A group of people showed up at my house and had proof that my soon to be ex husband had been talking to underage girls while i was in the hospital. About a month later a video was released that was the group of people interviewing him. He was arrested two days later on child sex crime charges. I have since struggled to support my family as he was the main source of income. I filed for my divorce and he wants visitation with the kids. I dont want him having visitation at all but if he does under supervision. He has hired an attorney and plans to fight me on the custody of our children. I dont have the funds to pay $2500 for an attorney but i need one to make sure my children are safe. And to be able to change their last names so they are not associated with him. Thats another $675. Im asking for help. Not for me but for my children. Thank you.