I haven't dated anyone who was an ENFP (at least not that I know of), but I have a friend who borders between ENFP/ENFJ. I love her dearly and she is one of the greatest, dearest people in my life. We have been friends for the last 16-17 years and have grown up through high school, college and adult life together. The things that I appreciate about her are the things that I strive to be, but often fight with. Most of my close friends are extraverted, rather than introverted, which I prefer, because I enjoy listening to them debate things while I have time to sit and listen and absorb and ponder. Sometimes, the extravertedness can become an issue. We have times when I just don't want to talk about things, and she insists on prying until we get to the bottom of whatever is happening. For me, I'd rather stew in my own juices, come to a conclusion (which will later change, of course), and then discuss it. Sometimes, we have to take a break from each other (we were very close and spoke daily for a number of years) and then come back to the table.

Now, I know none of this has to do really with your question about a relationship (which I assume is a romantic one), but I did work in a career office for a university for some time and the counselors (though I am not one), pointed out to me that there are actually quite a few differences between ENFP's and INFP's. You'd think it's just the extroverted vs introverted point, but if you look at the actually personality descriptions, you'll find some similarities, but many differences as well. I believe as long as you're willing to work through differences (in any relationship), you can make it happen. :o)

MBTI looks at the functions of INFPs and ENFPs differently than Socionics which says that INFPs are introverted intuiters and extraverted feelers, and ENFPS are extraverted feelers and introverted judgers. MBTI says that INFPs are introverted feelers, so many of the MBTI descriptions of the INFP really belong to the INFJ. I test as an INFP in both systems. I know lots of ENFPs and lots of INFJs and they are very similar in the same way that INFPs and ENFJs are actually similar. As an extraverted feeler, I think I am almost incapable of giving people the silent treatment, or holding on to grudges over things that are long gone. ENFPs in my experience are incredibly fun and seductive people when there is no misunderstandings, but if you accidentally upset them somehow, they will not tell you or talk it out, but will instead avoid you thinking you should know what you did. One of my best friends is an ENFP and we go through periods where she won't return any of my calls and we don't see each other for 6 months or more, though she tells me now that she's through with that. We'll see. My exboss was an ENFP and couldn't face the negative things I told her were going on in her department, and instead of fixing them, she lied to get rid of me, so she could go back to pretending everything was OK. I dated a girl who was an ENFP and she gave me the silent treatment with no explanation as well. I guess I'm scared of ENFPs because I know how energized and fun I feel when I am around them, and how rejected I'll feel when they decide to move on with no explanation. I haven't actually known many male ENFPs so I'm not sure if there is much of a difference in the expression between the masculine and the feminine.