Because I used to be manipulated by both my stepmum and Dad to a degree (pushed they're distorted perceptions onto me), it's why I've had to take special care in reading about manipulation. I am quite naive to impressionable people, so I've had to say to myself 'Keep guarded, don't trust people immediately just because you lack what they have'. In other words, not to idolize others and keep myself in check. It can be hard.
The previous person I dated for only a few months was big on playing games. She had very little empathy with what she was doing. It hurt me very badly and took me almost a year to get over the intense emotional overwhelming of it all. At the end of it I apologized to her for my mistakes. But I did not receive an apology back or even a recognition that she had been very cruel at times.
My housemate is not a sociopath but he sports a lack of empathy at times where it's needed. i.e. he cheats on his girlfriend. He's done it in front of me. He has no guilt for what he does. It puts me in a stalemate situation because she lives with us and I like her. I've had to keep in check that this is part of his personality. Unfortunately I become quite distrusting of such people and have decided to keep some distance from him. In my experience, such people have hostility locked in them that can come out in whatever way that might be unpredictable. Not always, but sometimes..