My Culture?

So I've been living in Japan for a few months now. And it's been... interesting. Can I say that it was even more difficult adjusting than I had thought? Like how I told my sister (who I'm living with while I'm here), last time I came to Japan I knew I was going home after the summer was done with. But this time it's different because I'm not going home to Thailand, after these next three months are over with I'll be going to the States (I have the smallest chance to visit Thailand for a month). There's something daunting about going back to the Sates. Maybe because I've learned while I'm here is that I do lack 'American grace'.
All of my siblings have grown up in Asia. My sister lived in the Philippines for ten years before we adopted her then lived in Japan with us for two before going to America for the first time and of course both my brothers lived in Japan for two years then Thailand for a number of years. Then there's me. Me and my sister got on the subject of our upbringing and how different her's was from mine (she is eleven years older so there was a difference in upbringing) and with a chuckle and shake of the head she said, "You are the most Asian of us all." I had never really thought of that before. I had never really considered that I was very Asian. But as I had written in my blog post about being a TCK, while in Asia I'm American, but while in America I'm Asian. So kind of a lose lose situation there. It's confusing and just... strange. I don't like hugs, I don't really care much for hand shakes (really just human contact with people I don't know is very uncomfortable), and how familiar people are with each other.
Growing up in Asia, I learned that you don't get too close with people, you don't act like they're your best friend when you first meet. But with Americans, it's different. They act so casual with one another, it almost reminds me of Filipinos and how, after one meeting, they're like best friends. It's odd. But then there is still that distance between two people when they first meet. So my question is almost always, 'how close is too close?' Because they're acting like they've known you forever, but then you ask a certain question and you're both strangers again. Like I said, it's odd.
And once again... it's been difficult. Besides my whole family being scattered across the globe, deep down I'm a homebody. I like to be close to my parents (what can I say, I'm the baby of the family?) and don't care much for things changing. So it's been difficult adjusting to the different culture and all because it is so different and let's also add that this is the first time I've been away from my parents for a long time (again I'm the baby of the family).
So while it's been fun, I've got to hang out with my sister more than I've been able to before and get to be around her family. I get to live in Japan again, I have great friends. But homesickness still hits me... I begin to miss the people I left behind there.