How Fe and Fe types deal with their emotional extremes
Fe egos need people. But need isn't quite the right word because it implies a sort of conscious desire that they wish to be fulfilled. It's closer to having someone (or multiple someones) with which they can share their emotions helps them rationalize and deal with their own emotional world. Fe ego types are the epitome of "Misery loves company" and "Happiness is best shared". In the former, sharing their sadness helps them understand and deal with their sadness. If they feel poorly, or negative in some way (anger, sadness, ect.) sharing that feeling shortens it's duration and while not lessening it's intensity enables the Fe ego to deal with something that may have otherwise consumed them. In the case of the latter, sharing their happiness is something that makes Fe egos feel even better. However, it's not so much the act of sharing so much as it's actually seeing that happiness reflected in the people they are trying to engage.
In the case of Fe dominants I think that the concept of them being completely unable to ignore their emotions, the view in which their emotional world is something they are 100% involved in at all times, isn't quiet right. Instead I think that to Fe leading types their emotions are something that is, if they try to ignore it in favor of focusing on some task that needs doing, an unavoidable and unconscious distraction. A sad ESE or EIE doesn't just fall on the floor and cry about how sad they are because their emotional world has essentially consumed them. Rather they are actual people who, when they feel sadness, are still able to recognize when they need to set their emotions aside. This is most efficiently done through sharing their emotions with others. Though in the case of Fe dominants this isn't something they try to do, they just sort of naturally express themselves to those around them. There is no need to seek out others with which to share their emotions because they are constantly sharing it without even thinking about it. Unfortunately however if the ESE or EIE can't share that emotion or for some reason is unable to interact with those around them then their emotions really do become insurmountable in their eyes. They may actually be unable to function because their emotions so completely consume their thinking effectively prohibiting them from focusing or even thinking about anything else. Likewise happiness to a socially isolated Fe lead may feel incomplete and not last very long. They need to see their emotions reflected in others so they can feel justified in their expression.
I think that a lot of what I said about Fe leads applies to Fe creative types too, with a few minor revisions. Fe creative types are people who are certainly much more adept at dealing with social isolation, while it's not favorable and may lead to an overall decrease in their psychological health if it occurs at length, short or temporary isolation doesn't enhance or detract from their perception of their emotions to the same extreme. Having someone with which they can share (and see reflect) their emotions has the same positive effects as with Fe dominants, but not as severe negative consequences if they can't. I think Fe creative types realize this desire unconsciously as well. However, instead of broadcasting their emotions in the same way as Fe leading types they more readily seek out an individual whom they trust and feel close too and prefer to share their emotions (the more extreme ones) with that person. Not to say that Fe creative doesn't broadcast it's emotions, it certainly does, it's just that the desire is to share it with an individual. They need to share their emotions with someone they are intimate so that they complete the experience. In the case of positive emotional extremes I would think sharing the experience with someone they are intimate would be more akin to 'icing on the cake'.
With Fi creative types their emotions are something that they certainly have an intellectual understanding of however, in the same way as Fe dominants, are constantly distracted by emotional extremes they experience. So even though they may understand how they feel, and may know how to make themselves feel another way, they are too distracted by their emotions in the moment to effectively implement the change. Though instead of seeking out others with which they can share their emotions they instead need some sort of distraction from they way they feel. This distraction may certainly come in the form of social interaction with a close friend or a group of friends but it could be anything as simple as Sudoku or as complex as video editing. This allows them to distance themselves from their emotions and reflect on what the problem actually is. Fi creative types know, with almost complete certainty, how they feel but generally the experience of the emotion itself distracts them from actually being able to figure out why they feel that way. Not to say that if questioned a Fi creative type couldn't answer the question "Why are you happy?" It's more that veracity of their answer is less important to them than the actual feeling. In moments of extreme sadness however understanding why they feel sad is much more relevant to their ability to cope with it. Like the socially isolated Fe dominant, a Fi creative who for some reason is unable to distract themselves or focus on something else is likely to be consumed. They need distance from their emotional world so they can understand it.
It might be worthwhile to note that Fi creative types would be most likely to (and fairly effectively) hide any emotional extremes they are feeling while in a social setting. Though they may seem distracted as this occurs, unless someone is very intimate with them, generally others can be unaware that anything is going on.
Ironically Fi dominant types are almost as expressive as Fe leading types though in a much subtler way. Rather than actively express how they feel and try to explain this emotion to others they instead let their emotions color their interactions with those around them. A Fi lead who is feeling very negative may be curt, short, and to some extent rude to the individuals they perceive as the cause of the negative emotion. In a very indirect way this is how the Fi lead informs the offender that they have done something wrong. Though they can still be amiable with individuals who are not perceived as part of the problem in spite of the fact that they feel poorly. In fact Fi leads are very inclined to apologize for their behavior preemptively if they feel upset, because they are aware how their emotions make them interact with others, while not feeling the need to get into the specifics. Such apologies are often unneeded however as the Fi lead is in much more control than they think and their interactions with the people who haven't offended them may be just as amiable as usual. Being able to cope with and control their emotional world for the sake of focusing on some external task or desire is something that Fi dominants naturally see the value in and so often are very capable of changing the way they feel through the use of some external pleasure that they know makes them feel a certain way. It could be as simple as listening to an album they really like, going on a hike, taking a relaxing bath, or listening to the voice of someone they love. Even in instances where controlling how they feel is unnecessary for some external reason they may still engage in trying to affect the way they feel: the Fi lead simply doesn't like feeling poorly and knows how to change it. The problem arises when external needs or desires prohibit them from engaging in the activity or interacting with the person that will affect them in the way the desire. If an Fi lead isn't given this breathing room their rude behavior towards those who have offended them may inadvertently slip into their interactions with those they are amiable. In most cases Fi dominants are opposed to emotional probing, if they want to explain what's wrong they will and excessive inquires as to the problem may agitate them further. They need to be trusted to deal with their emotions.
Edit: I know I probably didn't say anything that's actually new to anyone. I think most of this is stuff that could have been learned from any of the various socionics resources. I just hope that, barring slight inaccuracies due my incomplete understanding, I made the information easy to understand.
That and I needed to procrastinate writing my communications essay for two hours so I could make absolutely certain that I got no sleep tonight