The people everyone describes sounds hauntingly familiar. I must have that ability to spot them because the people who you've written about are the ones I keep far away from and stand on guard when they are around.

I find they're usually the charismatic ones and that's how they get you-they've got that charm and they know how to say what you want to hear.

Like Perzephone does- I've learned to ask them a lot of questions. They usually lie a lot too and I like catching them in their lies.
They do get to me, sometimes, though. My oldest sister, especially. I've looked to her for love and support but soon realized she'd stab me in the heart before giving me anything. Live and learn.
Keep your eyes opened, TraceyLee. You seem to be struggling with this. TRUST YOUR INSTINCTS!!!!