Idk what to do anymore

I moved in with my boyfriend about two months ago. So this is how it happened, i grew up with my grandma on my moms side of the family, i met my mom when she was pregnant with my 6 year old sister, i moved in with her about three and a half years ago, one time she decided to take me to meet my dad and two of my other siblings, then we moved there, a completely different state and i knew nobody. A few months after that my "dad" kicked my mom out, she moved back to oregon and i stayed in cali. The rape started a little after that. I didnt know how to make it stop without getting sent back to my mom and never see my 12 year old sister who had just became my best friend. I didnt say anything and i even made everyone believe i was having sex with a random person because my sister caught me with a pregnancy test. I guess what im saying is i pushed what was happening to me aside and never really dealt with it.. Now that im not living with my dad anymore, im having nightmares about it and i wake up and dont even want my boyfriend to touch me, he wants to have sex all of the time but half of the time i cant even hold his hand without feeling disgusting, its not him, i just don't feel like he should have to touch me when im so gross, i just need some advice on how to talk to him or how to stop feeling like this