The ESE and SEI I know: the ESE treats everyone the same amount of Fe, yet is so self sufficient they don't seem to need friends. The SEI I'm close with has suffered a very tramuatic past and amoung other hurts, scars, and coping habits, has become very introverted and shy's away from many people. Which is a shame for me to see because this person really is so vibrant (jokes, teasing) and likable; all the best parts of Fe. The trouble is the negative streak in SEIs combined with introverted sensing which leads to isolated nesting.

Some of this might be explained that Fe =\= sociability, which is what many assume of alpha SFs.