One of the keys to the successful relationship my husband and I have is our mutual interest in personality types. His preference is Myers-Briggs, mine is the four temperaments. Understanding each others personality from the get go was huge for us to understand how to communicate with each other. This saved us from a lot of misunderstandings in the beginning and continues to be useful to this day.
(also very important for relationship harmony- understanding and utilizing the five love languages).
However, while my husband's Myers-Briggs is pretty iron-cast, mine is more difficult to understand. This is because both my Aspergers and hearing loss affect my natural function, making it hard to pin down what I actually am. I seem to be an ENFJ, but Nathan sometimes thinks I'm a P, and other times that N can take on S tendencies. Also, I can fit the profile of either an ENFJ or an INFJ, even though I'm definitely an extrovert. Why?
Let's be clear, I love people. If I don't see people all day, I practically knock Nathan over in my excitement to see SOMETHING ALIIIIIVE. And I process everything aloud. If there is no one around to discuss my feelings with, I just talk to the air. And I write best when I'm in a busy coffee shop, surrounded by people.
On the other hand, if I hang out with someone for more than a couple of hours, my body starts wearing down from all of the lipreading, and if it's not someone I'm really close to, it can get stressful to go on interpreting body language for a long period of time. And going out in public for a long period of time exposes me to a lot of stimulation that is hard for my Aspie brain to process.
(For perspective on how big of an issue that stuff is: my audiologist has said repeatedly that he's never seen anyone function as well as I do with as little hearing as I have - and I have to sleep at least 10 hours a night to recharge from both the lipreading and the simulation stuff).
So that leaves me as a strong Extrovert who absolutely has to function like a strong Introvert to stay healthy and sane. Working from home is essential - but man, Facebook makes me soooo much happier.
I still find Myers Briggs to be tremendously helpful, because it does work for most people and understanding that someone is a P instead of a J is going to help reduce my stress when I know they're not going to arrive on time because P's just struggle with that. But because additional physical and mental factors can really affect the true personality, I rely more heavily on the four temperament system because it is applied rather differently and is easier to apply even with additional factors (for those who wonder, I immediately identified that Nathan was a Phlegmatic Melancholic, which proves more and more correct all the time. I am a Choleric Melancholic, but I am learning to be more and more balanced every year).