help...it freaks me out😖

So a long time ago (maybe 4-6 years ago) I was molested and so anything that's had to with being the slightest bit of sexual freaked me out wayyy more then it should and a few months ago me and my bf started having sex and just recently every time we have sex or something it makes me freak out cause of that horrible memory. When he starts to tease and I say no stop it playfully like a "do it anyways please" it still freaks me out when he keeps going and idk why... help😕 idk what to do about this and my bf doesn't know bout how it freaks me out...