The concept of "family" for Chinese people is totally different from the one held my many westeners.  Here in China, family unit is highly held, and in a very close relationship.  In fact, it is common that sons and daughters many times, even after marrige, do live with parents for a while, saving to buy their own place eventually.  Besides, in today's Chinese society it is very common for grandparents to actually take care of children while mama and baba work each day.

So, if you are interested in a steady relationship with your current GF, or with any other future one, you must learn and accept that here, you just do not gain a GF or a wife, but the whole family too.  It is their way of life, and anything not along those lines, will be misinterpreted by them.

So, learn to be patient and put up with it, if you really value your relationship.  One thing I have learned is a few chinese games, like checkers and poker (chinese style), and it does help me pass the time, and I am doing something they like and enjoy.  I am learning now Mahjong.

You are indeed fighting a uphill battle and quite frankly, I don't like your odds here. Especially since you are already getting tired of it. I'm married now and since that day, the time spent with the inlaws has doubled. And they have no problem with the "drop in". By that I mean, they will drop in on you guys. My biggest beef with it, even though I understand the family dynamic, is the constant visiting for no apparent reason other than to eat and watch tv. It's draining but I knew that going in. .

If you don't make your own plans and be clear from the onset that you also need your "me time" you will be engulfed by the great togetherness package that is the Chinese family unit. Again, be clear and firm that you will have your own time.

Oh, and as Happy said, if you are really serious about this girl, Mahjong will do wonders for you.

Your girlfriend and her family are a "pckage deal" so unless you are willing to run away with her to another place, the sooner you accept this the better. If she feels that you do not like her family the same way that she does, your relationship is doomed to failure.

If you do not talk that much talking more with them find common ground if that does not work. Do what I do find something to do before hand and show up later, that way you spend less time with them and everyone saves face and it is all about the face man.

Who has good excuses for him coming later in the day to meet his girls family use comments?

If U marriage U will probably spend your whole life with mother in law. Anything else will be strange.

Denying your mother in law is a big let down, you will be screwed in this life and in your afterlife.

Welcome to China!

Do you two have your own apartment? Is your gf the only child in her family? Does she has brother or sister? If she is the only child in this family, maybe you have to do this. If not, maybe you may talk with her about this.
 
Exchange ideas on family and job, hope you may find a way.

If you're not married then cut it down to once every two weeks. Have her explain that you don't understand what's going on.