Perhaps it is fitting, a day before your 23rd birthday, to be writing yourself a letter for the future. You're in a strange place at the moment, and even though you journal and analyze (and overanalyze) frequently, you may want the kind of clarity about this portion in your life that only a direct communication can provide.
The thing about you, Pickering, is that you seem to have to learn the same lessons over and over again. Before you go chastising yourself for a slow learning curve, or begin to fixate once more on the growing apprehension that that's pretty much how life works, take a moment and breathe. At worst, you are giving yourself the advice you'll (still) need two years from now; at best, you are reflecting on a moment of serious transition and growth in your life.
First, allow yourself a modicum of pride every now and then. It is not hubris to applaud yourself for your successes. You've lived on three continents, studied and worked in some of the biggest and most fantastic cities in the United States, managed to graduate in spite of taking a semester off, and most importantly, have been consistently blessed with fantastic company. At age 22, you moved alone to a new country whose words you could not read, whose food you did not know, and whose people you did not understand, and now you've made a true home for yourself there. Remember when you first arrived? The culture shock was so thick, so penetrating, that you lost your appetite. You forgot to eat for hours, sometimes even days. The smallest tasks - withdrawing money, buying milk, asking for the restroom - were tedious and draining. You were so terrified on your first day of school - am I bowing right? Do the students already know this material? Did I pronounce her name wrong? - that you promised yourself you'd only stay for one year. And now here you are, one month into your second contract, and there isn't a single inch of your town you don't know, a single student you don't love, a single weekend you aren't excited to roam the back roads of your second home. Don't short change how difficult that was either, learning how to span the gulf between two worlds. The things you had to lose first, to gain a life here. Time, with your sisters and their children, with your mother. The sense of identity derived from being a leader at your university, in your student organizations. A fiancé, and the relationship that fell apart when you moved and he wouldn't come with you. Yet what you gained in exchange for that - the pride when one of your students asks you a question in perfect English, the sense of accomplishment that comes from correctly reading a sign in Hangeul, or understanding when someone speaks to you - was the total ownership of your person, your life choices. You know now that you can make a life for yourself anywhere, not because you're done growing, but because you've equipped yourself with the tools to rebuild, wherever you go. You have conquered, and no matter what comes in your future, you must always remember that the thing within you, the spark that has propelled you forward, will only continue to grow, to fan the flame of your passions. Whatever happens, you will succeed, even if you fail a bit, first.
Second, be at peace with things. That's all. You put so much pressure on yourself - as a daughter, as a sister, a girlfriend, as a young woman starting her career - that in these moments of great tumult, if you lose sight of any of those definitions, for even a fraction of a second, you seem to lose yourself entirely. So be at peace. If you aren't at Harvard in two years, OK. You will be somewhere, and it will be fantastic, and if it isn’t, you will make it so, because you have before. If you and J don't work out, OK. Relish the blessing of meeting someone so spectacular while here, and having had the companionship of such a wonderful man, for however long it lasted. If you haven't finished (and published) your book yet, OK. Keep going. If your family still doesn't understand why you travel, why you've left, OK. Accept that they still love you, in their own way, and remember that the only person who will live your life for the entirety of it is you, so make it a good one. If all your plans have fallen through, and all your dreams have changed (again), OK. Be at peace. Whether or not you go Ivy League for graduate school, or have your heart broken a hundred times, or ever publish a single piece, remember: you define you. You choose your character, your mindset, your path in life. So be at peace. You will figure it out. Stop punishing yourself for not having it all figured out in your early twenties; that's not the point. Maturity isn't a race. Be at peace. Love yourself, whomever you are, and be at peace.