Partner is way to sexual

So my boyfriend and I are into DDLG, but my boyfriend is also into... other stuff. He's almost obsessed with the idea of me fuckng someone else in front of he. He constantly talks about it, begs me to sext him, has me send videos pretending to be fucked, even pulling the "I'm daddy, I'm in charge" card. He knows it makes me uncomfortable, and I'm scared to tell him things, like how close me and my roommates are, because he will want me to fuck them! I try so hard but Idk how to fix this.