I've been molested, statutory raped and am being blackmailed, help?

Well last thanksgiving my cousin molested me and I told my parents about it, he really didn't get in any trouble. It was partly my fault I blame myself for everything. Then this week I hired a new tutor he is 18 turning 19 and I just barely turned 16. He told me to get his trust I would send a full nude shot of me with my face in it. He called it his insurance for being telling anyone and pretty much said he would show it to people. He told me that when he tutors he likes to reward his people every time they do something good. He told me he wants to do dirty things to me I played along but then he stuck his hand down my pants. Then last Wednesday he came over and we had sex. He didn't want to use a condom but I made him. But who cares because it broke anyway. It makes me think he has done this before and he just creeps me out. And I was just manipulated and taken advantage of because I just came back from rehab for self harm, suicide, and an eating disorder. I don't know what to do I'm ashamed and feel like its my fault. Could he get in trouble with the cops. Because my parents when I tell them might want to call the cops. How can I control my urges for self harm ?