Of course, I do feel a responsibility of saying "never diagnose yourself", so there I said it.
That being said, I do understand that the ENFP, given certain environmental factors, could possibly become a BPD. I think we are manic by nature. If you do feel like this is an issue and you are struggling to maintain normalcy in life/ relationships/ etc., there is no harm in talking to a professional.
I don't have BPD, but I have wondered if I have cyclothymic disorder. It's a mild form of bipolar disorder, in which you go up and down with mania and depression but not to a severe degree. While sharing certain traits, bipolar and BPD are very different in origin. Bipolar disorder is mainly due to chemical imbalances and BPD is usually an environmental influence. I go through bouts of high energy, excessive talking, no sleeping, complete joy or extreme irritation, jumping around from idea to idea, needing to physically keep moving for days and days, if not weeks. Usually I come down to stability, and rarely I go through bouts of depression.
I solve this a variety of ways. I am on a thyroid medication that raises my energy, so sometimes I take a break from it for a couple days. Eating nutrient rich foods and getting daily exercise also helps. I avoid junk food and processed sugar. In addition, I take fish oil twice daily because it is an anti-inflammatory that helps regulate mood sings. If I can't sleep, I take a sleep aid.
Have you ever watched "Girl, Interrupted"? Winona's character exhibits signs of BPD.
I grew up with a mom who had BPD. She vaccillated between the witch and the queen. I also dated a girl with BPD for 4.5 years. (My first relationship - I thought being that wacky was 'normal' for girls.)
Both of my parents were severely disturbed individuals. They just kind of fed off each other and they both snowballed.
My advice would be to be very cautious about having a relationship. People with BPD are energy and emotional vampires. To a person with BPD, your partner is someone who you intend to use for your feeding frenzies...someone to use and abuse.
My other advice would be to never, ever have children. The lifelong effects on children raised by BPD parents should be enough to shock any normal person into not having kids. (If you lack the empathy that you are not shook up by learning the effects of growing up with a BPD parent, then you probably have BPD.) Please understand that the effects on children of BPD parents are so severe that therapists can do very little to help them - they try to teach you how to live with your issues, instead of fixing you. Growing up with a parent who is unable to feel empathy, and nurturing and raising the parent (role reversal, instead of the parent raising the child) have devastating, life-long effects.
I researched the same for my personality, the impulsive reactions I do to ease emotional constant discomfort and unhappiness made me question my sanity.... I tick all the boxes but I know I'm sound of mind, it's just an emotional kink that needs to be sorted out and improved on... When it comes to making decisions about my own life I am horrific and my emotions cloud my better judgement. Instant gratification is a problem, but that's just my personal experience when I was going through the same thing and question.... Just a thought