I just reread my post and I wanted to say that I'm not trying to be overly harsh to INFJs. Most INFJs I know are wonderfully sensitive and intuitive people. But I think this is an inherent weakness of the INFJ personality.
All personality types have inherent blind spots.... including ENFPs like moi. (We could do several threads on ENFPs inherent blind spots.)
I think the trick is to balance ourselves. Don't use the cognitive process we're most comfortable with (which for an INFJ is Ni followed by Fe). Use the process that best fits the situation. This means using a little Ne or God forbid Te if the situation calls for it. And, it seems like a little T (either introverted or extraverted) might be a useful cognitive process before taking such a drastic and often irreversible action.