Isabeau-
I am sorry you have had some negative experiences. It is so messed up that everyone can't just be for real and direct.
To help answer your question, I would like to ask what exactly happened in that you got burned?
For me, I don't know if it's luck or intuition or both, but I have never met anyone who turned out to be a fake or a sociopath. (they just ended up leaving me, but that's another story! lol).
I just get a sense about people when I'm talking to them, online, then on the phone...
I know I ask _A LOT_ of questions, a lot of difficult questions as well. If I feel someone is backtracking in a story, or tells me one thing than something else another time that sounds like it doesn't mesh- I confront them on it (politely, but directly) and see if their reasons make sense.
I also am very direct myself about who I am- good and bad things. I lay it out up front- my picture, my weight, etc.. So, that may encourage the directness from others as well as scare away those who do not want to be real.
Last note- you do have a great resource right here on this site- I suggest the next time you are talking to someone about possibly meeting, if you have any questions or hesitations, ask someone here. If you have that tiny voice inside you saying, isabeau, this doesn't feel right... LISTEN... and then you can ask someone here about it as well.
I also invite you to ask me anytime if you have any questions like that.
-Ep