I usually start to really miss China after about a week, but I'm always glad to leave Beijing for a while during winter.
But since my immediate family is also here, I don't have much to look forward to "back home".

You have become truly "multi-cultured (as oppossed to "multi-cultural)." The difference is that, in the first instance, you are able to operate in both cultures, which shows a familiarity with what to expect as cutural norns in various societies. This can be good, and bad. I've read reports that those who have long term exposure to other cultures no long feel at "home" in either setting.

Don't know if that is true or not existentially, but I've been here two years, and only went back home for 30 days last July. No reverse culture shock, no unfulfilled expectations, no kissing the ground upon arrival. The experience was pretty benign. Actually, it could be described as rather sedate on my part, but I went mainly to show my wife off to my family and to give them a chance to meet this wonderful lady I'm married to now.

China: the chaos, the crazy behavior, the growing pains, the "I can't believe I just saw that" moments; all the differences that make "here" here and "there," there, along with the chance to explore a whole new country makes it exciting for me. Attraction and repulsion are strange bedfellows, but never boring.

So, in answer to your question, I would say it was both. This isn't my home, but it is my wife's, so that allows for a certain amount of "grin and bear it!"

I just got back the other day, and on the way I was feeling like crap about it. Sick to my stomach even, not so much now though. I seem to adjust to either place immediatly though, but it still is weird to speak English all the time to strangers.

I usually go through a roller coaster of mixed feelings about this. I was so pumped up about going home for Christmas for months leading up to the departure date. I was so eager to leave China for a few weeks. But when I arrived back home this time, I didn't feel as excited as I expected and even started missing China. Then closer to my return date, I dreaded going back to China and wanted to stay home longer. Now that I'm back, I'm dreaming of my next trip home already, whenever that may be. Weird.

I went back home for a 10 days visit almost one year ago.  Had to resolve also some unfinish business related to the sale of my business there.  I had grand expectations, in a way missed many things, like a thick medium rare prime beef and bake potatoes, a real ceasar salad and onion soup, besides coffee.   My trip to the restaurant was a fiasco, no onion soup available that night, had no anchovies not olive oit to make a proper salad, and my thick prime beef was maybe under 1/2 thick.  Then paying $ 120 to a taxi to take me to my brother's home, and many other small things.  I really could not wait for my return, and was glad when I finally got to "My Paradise" (that is how I call my apartment) here.       

I go back to the UK twice each year for business. All it is for me is a chance to earn some money and then come home, back here in Nanning. While I am in the UK I catch up with my sister and her family but apart from that there is nothing there for me except being able to earn some money. What I earn there in a year pays for five years here. If I were rich enough I wouldn't bother at all, apart from my sister.

Haven't been back to the US in almost 5 years.  I am supposed to go back next month for a couple of weeks.

My friends have all moved on with their lives.  My family was never a 'comfortable' group of people for me.  So there really isn't anyone there I am dying to spend time with.

Food.  There are several places on my must eat at list.  Currently, near the top of the list is any cart (normally there is one outside of any Home Depot) that sells steamed polish sausage on a bun.

But aside from that, I don't know what I will do with my time.  The last time I went back for only 10 days.  By the third day I was so bored that I started thinking about getting a tattoo just as a way to occupy my mind.

It is strange, but I actually feel a little guilty about how much I miss living in China when I am not inside China.

After the honeymoon period ends I just end up missing China.

Well I guess I'm stuck in the middle...

I came back because I missed the place... and I and someone who had plans to join me.....

Now  my job offers me even more trips home, but I'm even more willing to stay here alone.... so either way is ok with me.

Then again I could wake up in France tomorrow and I'm sure I'd enjoy it

About as good as anyone feels going back to work.

I kind of have to agree with fish79. I think when I go home, I'll be happy I can see my friends, and I won't have to work (unless I get a part time job over the summer, which I probably will). Right now I am in Japan, and it's a totally different world. I don't get to eat beef very much in Lishui, so I've been eating burgers and gyudon, and it has beef without bones! Imagine that. I'd have to say the only things I miss from home are the food and my friends. When I go home I will probably get bored, since it will be for about 2 months. I won't know what to do with myself, so I'll probably be happy to go back to China.