Here's my theory on reverse culture shock. I think it makes a lot of sense. It's kind of deep but I'll try to put it as simply as I can.
The reason you feel withdrawn and disconnected when you come back to America after being abroad for so long is this:
You see, when you grow up in America, you develop a fake artificial pseudo-self in order to fit in socially and culturally. This pseudo-self takes you away from your real authentic self, which must be suppressed or subdued in order for your artificial "Americanized self" to win out. Even if this happens, and you become fully Americanized, you will still be unhappy because deep down you are fragmented and disconnected from your authentic true self. This, I believe, is why Americans look so angry, unhappy and dissatisfied on their faces, though they don't know why. It is also, I believe, the primary cause of the unusually high rate of mental illness in America.
However, if you don't conform and remain close to your true self, you will also be unhappy in another way, because you will feel lonely, alienated and out of place in America. The social culture will intimidate you and you will feel withdrawn because you can't be your true self. This is the reason why people who are really down-to-earth and authentic feel withdrawn in America and intimidated by its fake social culture. Have you noticed that? So either way, whether you conform or not, you feel unhappy in America in one form or another. This, I believe, is why America does not FEEL like a free country, even though it's supposed to be.
Now, when you go abroad, you are liberated from this dilemma. You see, foreign cultures in general are more authentic, down-to-earth and genuine. This applies to the people and social vibe as well. In such foreign cultures, you are able to
reconnect with your authentic true self which you suppressed in America. In other words, you are "free to be yourself" again. Your "true self" is allowed to come out. This is why when you are overseas it feels so LIBERATING and FREE. It's because you are reconnecting with your true self again, which was lost in the crazy madness of assimilating to American social culture. It's like you discovered a part of yourself that lost in America.
As Grunt said: "If anyone feels they "come out of their shell" when overseas, try to keep something in mind. That person you are overseas is the real you. The person you are in America is a prisoner, nothing more." - Grunt, from
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Now, when you return back to America again, here's what happens: You are faced again with a culture that expects you to become fake and artificial again, and disconnect with your true self. At that point your authentic true self cries out, "No way! Don't! You just reconnected with me again finally. Don't go back to your fake self again. Reject American culture!" And you know its right. So you listen to it, and as a result, you withdraw from American social culture and feel intimidated by it, because it's trying to get you to be something you're not.
You see what I mean? That's what's really going on with reverse culture shock. Now I can't speak for everyone of course. But I think if you are a deep, authentic, sensitive person like me, the above will definitely apply to you.
What do you think? Does my theory make sense? I think it does and it explains a lot. Every time I've gone to Russia and returned to America, I've always gone through that, and became depressed and withdrawn. I could not understand why or put it into words before. But now I think I can.