Why is it that psychopaths, narcissists and sociopaths seem to be the most charming people - certainly in the beginning of a relationship? The ones that sweep us off our feet and seem to know exactly what to say to when. They appear to magically and instinctively know how to get under our skin and make us comfortable - so we relax, let our guards down and let them into our lives. It is not magic though, nor is it instinctive. It is far more simple than that.
As teenagers and in our early 20s, most of us experiment with flirting/dating. You see a guy, or a girl, that you like and build up the courage to talk to them. If rejected it is humiliating and embarrassing. It is devastating. It takes it's toll on us emotionally and makes us wary of approaching others. It may take a few days, weeks, months or even years before we build up the courage to risk putting ourselves 'out there' again. So we select those we are attracted to very carefully and guard ourselves against emotional pain.
Psychopaths, sociopaths & narcissists all typically have little empathy and either dulled or no emotion. They are not encumbered by hurt feelings or embarrassment. If rejected they simply shrug it off and move immediately onto the next person they are attracted to only minutes later. Each time learning from the rejection like a computer programme. They can target dozens in one night until a strategy works. Over the course of just a couple of years they can target thousands this way - never feeling upset or embarrassed about the rejection. Eventually they have a full database of how to approach shy people, how to approach the life-and-soul-of-the-party, how to approach the single parents, the divorce, the injured and the kind-hearted. They know exactly how to react in each given situation simply because they have experienced it before many times.
So their 'charm' is simply learned behaviour from many many encounters - they know what works with each person and can adapt fast to accommodate what it is that WE want. They reflect our desires and provide us with tried and tested techniques to win us over. They look like they are handing us their hearts but in reality it is an act which has been polished over time - indistinguishable from the real thing and impossible for any normal empathic person to know the difference.
Ultimately, it is only time that shows us the truth of someone's feelings. If you have been caught by a psychopath, sociopath or narcissist then do not blame yourself for believing them. YOUR emotions were genuine, it is not your fault if theirs were not, nor were you wrong to believe that someone loved you.