Just hopped in at the end. As an INTP that has studied relationships, charisma, and power dynamics dating an ENFP is kind of tricky for an intp, but straightforward once you realize why she's into you.
First off they love you. Your seemingly endless depth as an individual will have them gazing into your soul for hours on end. Very easy to have a strong mental connection. What you have to understand is that enfps tend to have exacerbated pretty white girl problems. They went to high school with a bunch of attention seeking daddy's issues little boys and girls all mindlessly chasing status. And they're some of the flightiest of the bunch. Sound critical?
So analyze what happens in those scenarios. Plans are made, and plans are canceled. Communications and conversations are started and abruptly halted. She will have learned to fear deep connection as it leaves her delicate little flowery soul oh so vulnerable. Your best bet as an INTP is to put the fuzzy cuffs on her. Limit your communication to once or twice a day, don't seek connection. Just act as though you're already in a relationship and give her the constant consistent validation that she has never gotten from any other guy before in her life. Be like her dad. At some point, something will come up in your life, and you'll be like: "She'll love this." And she will. Then just resume normal conversation.
If she doesn't view you as more intelligent than she is, you might have to game her a little bit. I never bothered learning game, and simply continued developing my intellect, social, and connection skills.
Another important thing. Know how to spot passive aggressiveness. That's when in the middle of a conversation she stops responding, in the middle of a date she doesn't want physical connection, or she misses plans or other dates. This is all a protection mechanism to slow or stop connection. As much as we all DEEPLY desire to be seen at the deepest level a lot of people have learned to fear it as well. So if she misses a date, just say: "Hey, sorry you had to miss the date, I'll talk to you later."
Oftentimes their subconscious will literally over-ride their thinking logical side. So they literally didn't make a conscious decision to reneg on an engagement, it's just their 'moodiness', 'depression', or whatever label they want to call it. (if they feel powerless in their life, they'll do this just so they subconsciously get validation that they have control in their lives, yeah it's shitty, but it's what humans do)
I've just hopped into a relationship with a beautiful crazy enfp girl. She had been creating worse and worse abusive relationships due to her passive aggressive communication style. After getting pulled into a hugely co-dependent relationship, I INTP'd the shit out of the situation, and now we're good friends that are looking to hook up and share our passions. Good stuff.
OH AND SUPER IMPORTANT! Know what asserting yourself is, when and how you should do it, and why. Practice standing up for yourself. Get good at this, and the INTP can shine in almost any social situation.
OH AND ALSO IMPORTANT! Don't worry about getting hurt. Getting hurt is one of the more beneficial life experiences simply because as you feel shitty you learn to jump into each of those feeling states, experiencing them, and plowing through to the next emotion, to the next emotion, to the next emotion. It's intense, and can leave you feeling burnt out but each time you do it, you'll get better and better at processing life's challenges. It's called building character. Everyone says to do it, but they don't tell you how. So for example if you want to kill yourself, scream "I FUCKING WANT TO DIE". You really can't over do it. (unless well meaning peeps send you to a psych ward). You get past that feeling, and then identify with and jump into the next feeling state. So on and so forth.
