Ex boyfriend mentally harassing me

Hello. My ex boyfriend and i broke up a year ago. For some months we had no contact with each other then after some time he contacted me on his own and asked me a chance for which i denied. Then he said lets be friends nd all to which i again said no. All this went on and then we got on talking terms but i made him very clear that him and i will have no future. Every time he asked for marriage i said this. I did not give him the illusion that i will marry him and i also said that it is not because of my family. It is i who doesnt want to get married with him even if my family does agree. Then last he called me and said that his mother is forcing him to get married. So he asked me and i told him to go and get married i dont have a problem with that. I tried to make him understand that i never him such an illusion and i want to focus on my career. But he kept on threatening me that he will come to my house and talk to my family and all he wants is me. He has done these before and this was one of the reasons we broke up. He keeps on threatening me this way. I am really tired and am going in depression. Plz help me all i want is just to focus on my career and i have also made these things clear to him. But he keeps on harassing me.