So many cool people writing cool letters to their 13 year old selves--what is a girl do but follow their lead?
Dear 13 Year Old Me,
I sent you a letter a little earlier, but it got lost in the mail. Trust me, between time travel and the barely improved postal service in Iran, it was inevitable.
I can just see you curled up in an angry ball, glaring at the back of Brother #1's head. Take heart, you won't be sharing the hallway with your brothers and cousins for ever. In a couple of years, you will move into a giant house that will become The Family House, and you'll have more room than you bargained for (and you'll be doing most of the cleaning, but it is almost worth it). Until then, just try to remember to breathe and let go. I know you are scared out of your mind every time someone walks out of the house these days, but everyone will survive the war. Dad and uncles will be fine; Mom and aunts will not be hurt. Our homes will be damaged, but we will be fine. Bonus news: all your curses to Saddam will actually come to something--which is even worse than him getting away with all the shit he's getting away with now. But between now and then, just remember breathe and stay out of grown up battles that have nothing to do with you.
I know everyone has an opinion about what you should do and be, but you need start learning to say 'No!'. This is the most important bit of advice I could give you. Don't wait until you're 18, because it will be too late and everyone will think you're being cute--and promptly ignore you. Start saying 'no' even if you don't mind what happens. On a related note, stop caring what people say about you. You will get away from them (geographically, you will escape to sweet, sweet freedom), but if you don't stop seeing yourself through their eyes today you will never get away from them--and you will make my work MUCH HARDER.
(On a slightly lighter note, convince Mom to take you to Zartosht Street more often. There is an old man who sells books in the nook of the abandoned house who finds all kinds of English books. Be nice to him, he will be kind to you.)
Talk to people. You'll meet some great people in eighth grade and on through high school. Try to make an impression on them. Otherwise you will spend a good amount of time reintroducing yourself to people who sat next to you for years, because they never knew you existed--and that's just bad for your ego no matter how you look at it.
Make sure you spend time with Baba. Listen to his stories, hug him more, take him his tea in the afternoons and pick him some berries. He will look at you one day and not recognize you at all, but at least you will have your time with him and the happiness you brought him to comfort you.
Mom and Dad won't change--much. Try to accept them, but learn to say 'no' to them. Otherwise you will always be their Little Girl, and they will do to you at 23 what they do to you today--and you still won't appreciate it. That said, accept the crazy idea Dad comes up with after you graduate; it will get you to the US again and you will go to college (yay!). When you get to the US, think a little bit more about the stress and awkwardness that goes with your situation. It may not be ideal, but you're lucky to have the opportunity. Still, don't let gratitude stop you from speaking your mind (and occasionally saying 'No') and don't resist every little change--change is good.
College will be a roller-coaster. Don't stress so much! All freshman are as clueless as you are, just better at hiding it. Don't avoid the tall, lanky guy in your biology class. You won't get rid of him no matter how far you run, and he'll be a great friend anyway. The sooner the friendship starts, the better. Actually, despite your misgivings, don't avoid the Iranian students. You'll bump into a bunch of them years later and realize what great friendships you were missing.
You will get married, and to an Iranian (yes, you're right, you can't get away from them no matter how far you run)--enjoy the 'courtship'. You'll be glad he came to your life, despite all the bumps in the road.
I could keep telling you things--you know how we are with words and letters. But I've already mentioned the big things. You'll figure out the rest when the time comes. Just practice what I preached and we'll both be fine.
PS You have naturally curly hair. For the love of God start acting like a girl your age and start combing/styling your hair yourself. Otherwise you'll be sitting on the edge of a bathtub in a hotel in Chicago, hysterical that you look like Medusa.
PPS You're a horrible matchmaker. Don't even try. (Ok, try if you must, just be more subtle about it.)