My brother is ENFP and I'm INFP. I've always felt like INFP's can "pretend" ENFP in social situations where it's necessary (needing alone time later), but there are differences.
My brother is more likely to meet a new group of people and instantly like them. I, on the other hand, can be cynical of people who give me "bad feelings." I need more alone time than him (although he does need a decent amount), but the main difference is that I "live in my head," whereas he doesn't to the same extent. He has lots of creative ideas, but they're more about things to put out into the world (computer programming, ideas to help others), whereas mine are ideas I create in my mind to convert into mystical stories (different scenarios and conversations that can sadly never happen in reality).
In the end, I think we both understand each other because we understand how other people work. He can definitely ignore his negative feelings towards others better than I can. If someone gives me a bad "vibe" it's extremely difficult for me to be around them because their dark aura invades the room, but I bottle it up and don't say anything/find a way away from the situation. He ignores bad vibes better, but is more prone to emotional outbursts, whereas I take time to think about my feelings.
I'm not sure if that makes sense, but that's what I've got so far.