My neighbor keeps making false accusations to police, and my friends and boyfriend that I am a child molestor and prostitute. Do i have a case?

A guy I knew from a sailing camp when I was little keeps calling all my friends and family and current boyfriend saying I am a child molestor and prostitute. He accused me of touching him inappropriately and his daughter. I have had no in person contact with him or his daughter. I lost my apartment last time bacause of his rumors. He lues and calls the police everyday. He is mad I won't date him. That I am in a relationship with someone else. He stalked me down to my new apartment I moved a month ago, and now he is living in my neighbors house. The guy and his wife spread rumors that I murdered my son who I proved is alive and well. Do I have a legal lawsuit against this guy and his wife. I think the older gentleman that lives next to me tried to call the landlord and use a computer to impersonate little kids while I yelled at him to leave me alone and he made it sound like I was assualting children sexually and that I am inappropriate. He basically this guy and his wife ruined my life