http://blogs.psychcentral.com/childhood-neglect/2015/09/the-six-hallmarks-of-a-sociopath/
Six Signs of a Sociopath
Behaves in harsh and/or hurtful ways, and then expects you to have no reaction; to act like it never happened.
Manipulates others, either from the sidelines or directly.
Treats you very differently at different times or different days, for no apparent reason.
Lies easily when needed to get herself off the hook.
Externalizes blame. The sociopath does not take ownership or blame for his mistakes or misdeeds.
At times, appears to actually enjoy manipulating and/or hurting others.
Whether you know anyone who fits this profile or not, you’re probably wondering how to make sure you’re not treated this way. So here are some guidelines for taking care of yourself around a person who you suspect might be a sociopath.
Four Steps to Protect Yourself
Be on your guard at all times. Know what you can and cannot expect from the sociopath.
Avoid going to this person for emotional support or advice. Being vulnerable in this way opens you up to being hurt.
Imagine a boundary between yourself and the sociopath. Form a picture of it in your mind. Build a wall that you can see in your imagination that protects you. Everything the sociopath says or that is hurtful bounces off this imaginary wall.
Don’t make excuses for the sociopath. Instead, hold him accountable for his actions. The stronger and more direct you are, the less the sociopath will try to take advantage of you.