Daughter dating sociopath

I'm a parent of a 22 yo daughter who is dating a person with sociopathic behavior. She is intelligent and yesterday searched for information on sociopaths and emotional abusers. She is informed but admits she is drawn in wanting it fix or help him. She is flattered she is one of the few people he has ever let get this close to him. We, her parents, want to help but know our behavior may push her toward him. Advice? She is not yet in total denial.