My 5 is always clamped down on over expressions of emotion and fear and demands on others, my rationality always filters it all. But internally? Maybe not as much now in my life because I reached a place where I began to value my self, but damn, for my first few decades...
In Enneagram, being Reactive triad simply means looking for validation (in a sense) that a problem is real- either to validate their own experiences, meaning, and feelings (E4)
and
4s - introjection - blame self
and
4s without proper validation or reaction feel there is something wrong with them because 4s are inclined towards feeling they are defective
That is totally describing me earlier in life -- I would bear down with every ounce of rationality and independence I possessed to NEVER overtly request or demand that others affirm me because I felt like I was intruding and demanding something from them to ask for validation (which I as a 5 really despised when I or others did it), but I inexplicably also craved it, I needed it, I wanted it so badly.
Put another way, I was bleeding out internally ALL the time while putting up the detached stoic external demeanor where I had no needs and was unfazed by all the things I didn't receive from others. But you cannot ignore bleeding like that forever without any sign... so basically on occasion when something really triggered me or I lost my restraint, my closest friends/family would see me momentarily lash out with hurt over what I wasn't getting -- basically these expectations that they were not even aware of, so to them it was out of the blue and it startled/upset/confused them. Despite my typical easy-going appearance, those people also would call me "moody" due to these occasional blowouts / reactions to things I never voiced.
How I perceived it: I felt like I was always accommodating everyone else around me and being 'need-less' rather than needy like the rest of the world, and then felt horribly betrayed and lost, even though rationally I knew it was not fair to judge them if I never ASKED them or let them know i had this need for a connection or an affirmation of some kind. I just wanted a sign that they cared or that I had value to them. Or even value at all.
Because that was the other part of it. Most of my life i had no internal compass to tell me that I had value. I always needed it reflected from the external world. I've said this before, but usually in other ways. It's because I know my own thoughts but have no way to step outside of my own thoughts and judge my own perceptions and come up with the "right answer." Put another way, I can tell myself how great I am and how talented I am and what my "value" is... but is that a truth, or a lie, or how the hell would I even know the answer to that? I'm an unreliable witness because I'm self-evaluating. Nothing I tell myself matters. (or didn't, for a long time.) So I felt like I needed some kind of objective / external voice(s) to confirm for me what value I had. But I wasn't getting that reinforcement from anyone really.... I think in part because they didn't even know I needed it.
And the blame. I always self-blamed. Everything was my fault. Any conflict with another person, any accidental disagreement or embarrassing moment, any difference of opinion... there was always something wrong with me because I was the one who differed. I had my own convictions but never knew if they were right and hated it when others would assert theirs, because then I felt stupid and wrong regardless. Because I just wasn't SURE, I could be wrong... Anyway, you see where this goes -- it's a lot of self-uncertainty, self-loathing, and I got very little support from the "objective" external world to tell me I was on track.
There's this one bit out of "The Dark Knight Returns" by Frank Miller, where Two Face is looking in the mirror after supposedly successful face surgery to make him look normal again. (Harvey Dent basically had half his face burned off, hence Two Face.) Everyone else sees him as beautiful and normal. It's not until the end of his segment that you see how Harvey sees himself -- his face IS uniform in his own mind's eye, but after the surgery ALL of it is hideous now, rather than being uniformly restored. It's kind of how I felt. Others didn't notice anything; I felt monstrous, even when my rational mind kept telling me I was okay. It really was this huge 5 vs 4 tussle, and 5 dominated (barely), but it didn't stop the bleeding.
Basically in mid-life, i reached a point where I felt like "psychically" I died... I just couldn't live from all this bloodloss and lack of self-faith and self-loathing. Somehow in the middle of that, along with a few key people who treated me like a valuable person unconditionally, flaws and all, I got just enough validation to start to believe in myself and that -- even if I could never prove my perceptions were all accurate or worthwhile -- I "merged" with myself and took ownership and found value in those thoughts and feelings simply because they were mine. I guess in a way I finally embraced myself and gave myself value. I don't really know how that happens, but it took me so many years to get there. An acceptance of self, rather than repudiation of self and one's value? Basically I finally felt like I could listen to my inner voice and believe it.
I still appreciate validation but I stopped blaming myself for everything, and I started trusting myself at least as an imperfect human being and became okay with who I was. It seemed to get me past that huge 4 desperate need for external affirmation. I mean, I still hurt, when people don't validate me, but my sense of value no longer demands it. I know I have value even if I spend the rest of my life in isolation.