Baby daddy

I am 17 and almost 8 weeks pregnant my ex is 18 and said the baby was not his when I first told him now he wants to be in the baby’s life but he has multiple personality disorder and I’m scared to let him in the baby’s life. He will go days without talking to anyone when the other personalities take over I’m scared our child will get hurt because his/her dad will disappear for a week at a time because the person in control says “it’s not his family “