Jennifer and I used to be at (unintentional) loggerheads because of the misunderstanding (or just outright BAD experiences) with Fe. I'm so pleased we got that cleared away because now I have a great funny friend.
Fe vs. Fi. I have to say that I might not understand Fi at all if not for being raised with an ENFP. I might not fully understand Fe either. It seemed to be nothing but a blowtorch burning under my skin that I couldn't shut off or control. My sister's reactions to things sometimes seemed puzzling to me, and my reactions seemed like "THIS!!!" to her.
Fi's cooler nature can be enigmatic at times. Fe can be pyroclastic. Neither should be feared or avoided. My best friends are ALL Fi - INTJ, ENTJ, and ESFP. They know better than to be afraid of me, know better than to dismiss me by telling me to cork it. I know better than to demand or tax their Fi or accuse them of being heartless. Fi is very settling. Fe is tectonic. The two assist. I appreciate my INTJ best friend. Kooky guy. (Speaking of which, he just pulled up in the drive way. lol Gotta go!)
I've only dated other Fe's for some reason. We sweat it out the same way, I guess.