Ok, lets start off with something major:
Korea Life Lesson #1: No matter who you are, where you are from, or how old you are, living in any foreign country is going to CHANGE YOUR LIFE.
For the better or worse you will not be the same you when you come out of the other side of it, if you ever do. You will change everything. Your personality, how you deal with difficulties, the type of people you associate with, the list goes on and on. It is how much you fight against or go with these changes that will dictate how happy you will be in a new country. I'm not saying allow all the changes you see in yourself to solidify. There have been many times here where I've stopped, said "this is not me," and re-approached something from a different angle. I have embraced the newer version of me because, to be frank, she is everything I have always wished I could be, and more.
Us 외국인 (waygookin, Korean word for foreigner) have a term we like to throw around. It's "LBH" or "Loser Back Home." You will be out with some people, meet a new person, and suddenly, jarringly realize that, if you were back in your home country you would NEVER associate with this person. They are awkward, they are boring, they are annoying, but somehow they have heaps of friends and a super attractive Korean significant other. When you get here you get to decide who you want to be. To a certain extent, we are all here because we are LBHs. We were losing at living in our home countries. We didn't necessarily not have many friends, and we weren't necessarily failing in the workplace, but we knew we were losing and wanted to change something. However, none of us here are really losers, because most of us have made a bold, brave move that 99% of the people we knew in our home countries would never think of.
I have done things here I could have never thought I was capable of. I have seen things that I could have never even dreamed existed. I have met fascinating, boring, funny, depressing, wonderful, bland, exciting, and annoying people alike. These things shape you because, when you move somewhere foreign, they all come at you at once. You find a new place and you have 50 new names that you struggle to remember (don't be embarrassed, they probably don't remember your name either). You will be overstimulated in every sense of the word.
My only advice is to ride the wave. Know when to push against it and know when to just let it take you where it wants to go. Be flexible with people, both 외국인 and native alike. Never insist you have things your way and never insult someone for being who they are because, chances are, you have far more in common with that middle-aged, angry looking Korean woman than either of you could imagine (though I agree, that look she is giving you is terrifying).
Thus ends Korea Life Lesson #1!