@AuAL
What little I understand about the condition is that, from a physiological perspective, it originates in the areas of the prefrontal cortex and the amygdala. Coincidentally, these are the same areas that often affect social and psychological behaviors in ADHD and autism.
Furthermore, having spent a fair amount of time on this forum reading threads and posts, plus my own personal experience, varying degrees of RSD appears to be common within this group. I can remember, especially as a child, I would have one or two "good days" followed by one or two "bad days" in a depressed mood because of some sort of rejection over something. It was my life as a small child, but as I grew up into a teen, started getting into athletics, I gained a lot of confidence, almost too much confidence in some cases. I think in the more severe cases of RSD, it really holds people back in life because they lack the self-confidence, risk-taking behavior, and courage to "just do it". How can anyone gain self-confidence without challenging themselves? If you're in that depressed, fear-of-rejection, self-deprecating, self-sabotaging mindset then good luck ever being happy or excited about doing something you never thought you could. If you have ever seen interviews with successful people, it was perhaps years of 99% "NOs" before they received a single "Yes". The amount of rejection that must be endured along the way to success is beyond one's comprehension. It truly takes a strong-willed, passionate person to keep at it.
Personally, I am a "systems-type" thinker. I have alexithymia. I don't have a good relationship with emotions. I don't know what to do with them and it always leads to bad outcomes. Having said that, as a mature adult, I do have the ability to shut the emotion centers down and just function on my logic centers, if need be. I can be happy and sad, enjoy a joke, music, a sad story, etc. but if I get stressed for any reason, I just "click the switch" in my head and just function without emotions. It clears my head and is very useful.
At this stage in my life, I understand that rejection is just a normal, everyday sort of thing. I don't have to like it, but I understand it. I could let rejection shut me down,...or better,...I can run through you or around you and do it anyway. At work, I find myself playing the "long game" of
"How can I gain your respect?", "What are your fears and triggers?", "How can I make you a part of the plan?", "How can I give you credit and massage your ego along the way?", "How does my plan align with yours, to your advantage?", and so on. As I am writing this, it sounds diabolical and sociopathic, but when people don't want you to succeed for whatever reason, you have to keep them close, work with them, and give them credit when it's due as you march forward with your plan.