well, you can look up the definition of sociopath, but the gist of it is that they are very charming and "nice" on the surface, but they have a whole other side that doesn't come out until you cross them. i found out my boyfriend had been going behind my back every single day and picking up hookers and other girls on Craigslist to sleep with, and taking my money to fund a serious coke habit I never even realized he had. he was a totally different person to my face, professing his love to me, talking about our future together, etc. when i confronted him about it (found evidence in his emails), he became abusive and gaslighted me for months. finally he went to the police and lied and said that i had been stalking and harassing him for 6 months (when in fact he had been living at my house and sleeping in my bed until a week before) and i was arrested and went to jail. they dropped the case when they realized he was nuts and i gave them evidence to contradict his story, but a lot of damage was done. the day after i was arrested (10 days after our breakup) he flew some girl out from colorado to NY to be with him. she left as soon as she arrived and met him, and ran off with another man. he then hooked up with another woman who happened to be the head of the psych department at Riker's Island (prison) and Kirby State mental hospital. she saw through him and cut contact with him after 3 weeks- he had been proposing marriage and kids to her along with a lot of other erratic behavior and lies. she wrote to me and said that he is definitely a sociopath/narcissist. he has zero remorse for the things he did to me, and no empathy at all for how i felt. he used me and lied to me for 3 years, and then he was done with using me so he just got rid of me. it has been extremely difficult but i am in therapy and finding my way out of the depression that resulted. my therapist pointed out though that my mother is also a narcissist and that the feeling of familiarity and connection i felt with him probably stemmed from my relationship with her.