I just don't get it

I can call a situation in a bar or club like it I have some super power. I see people and just by waching a few seconds can tell you the turn out of a situation. Example a guy goes to hit on a girl. I can tell if he's in or out. What I just don' get is why I can't to the same for me. It's like this abilty has an off swich that my evil twin turns off. Am I doomed to make the wrong call for the rest of my life. Who knows. Maybe one day I will get it. I know that it just wasn't today.