Can I just chime in again that no, I don't feel I have an infp inside me. I also hope I don't have an intp inside me. I have an ENFP inside me and I have me inside me that struggles constantly to be out there and shine.
No offense, but as an ENFP and just me, life just seems harder as an INXP. I can identify sure, with a lot of the make up (or cognitive functions) of INTPs or INFPs and again, I have great friends of both types.
But, I really value and appreciate my extraverted functioning -- the fact I draw energy from the outside world and need to be in the mix and with people. Without it, I would not be who I am. Extraversion and the need and desire to be with the world stomping on grapes with the best of them, that is a core part of who I am.
I would not want to be an Fi or Ti dominant person, nothing personal. I just don't like how close-circuit those systems seem to me, I want to be with people and with the world, and though you can criticize Ne all you want, it at least prevents me from collapsing in on myself. Ne forces my being to pay attention to everyone and everything else around me.
INFPs and ENFPs are very different animals. Maybe made from the same clay but molded quite differently. This is why I like my INFP friends, we're from similar schools but very different people so we mutually pique one another's interest. This is also why sometimes I can get frustrated with them because I feel I can understand how they react to things but they reach very, very different conclusions and interpretations and ultimately make different decisions from me. This is why I don't identify with having an INFP inside me.
I think people are perhaps confusing true introversion with 'low' periods in one's life. Nothing at all wrong or judgement laden about true introversion, but just as it's stressful to force an introvert constantly in the limelight and force interaction with them at huge parties and schmoozing, it's stressful for an extravert to be forced into prolonged solitude, even even if it's 'self imposed'.
ENFPs, when you find yourself in that slump or too long gone in hiding, you're really just hiding from yourselves and how sensitive you are to the world. It doesn't work. You're not an introvert. You might be lazy (hahaha), you might be super laid back and go with the flow, but you're not an introvert. It's not going to sustain you in the long run or give you strength the way it can for a true introvert. And even introverts need to get out of the house once in a while! :P
Speaking of all that, I need to get my lazy, ennervated ass out of the house.
Amen... Totally second that...
Owhh, not seeing people is like a constant drip on your forehead; you'll last for a while, but after a while it drives you completely insane