Psychopaths are not always dangerous people. It's a personality disorder, not 'they will stab you' disorder.
They are reckless, manipulative, charming, sexual deviants, they lack empathy entirely and they are liars. You can't help a psychopath or change them, not without damaging their brain further and basically you'll be left with an empty shell of a person by doing that. It is a brain defect to put it simply, although really I don't view it as that. I think of it just the same way as I am a perfectionist, that is a flaw in my brain just as lack of empathy is in theirs.
My friend is a psychopath. I took the test for her as she lied on it. Scored very highly, this was with the proper tests done by psychologists (we were studying forensic psychology). She isn't a bad person or a dangerous one, but she doesn't know how to respond really to a person's problem. She is very charming, everyone loves her. Very reckless too she is always up for a challenge and doesn't once think about the consequences of what might happen.
They are not bad people. The very clever ones control most of the companies in Britain. There are plenty of people in jail who would score a zero on a psychopath test. The majority actually.
He is just trying to talk you back in if he is one and trying to gain your confidence back. Up to you if you fall for it, but you can't change his brain, he's stuck with it. No drugs will help that problem.