Yes,I have to agree with RT; move on. Life is too short to deal with being miserable for the length of time you've apparently dealt with it.
My guess is that your current students are mostly little rich kids and therefore the product of an upbringing that has left out even the time honored Confucian ethic of respect for teachers. Even worse is the fact that as they fail to learn or show progress in their studies the blame will fall on you.

Personally, I wouldn't put up with the kind of behavior you've outlined for even half a second. In fact, I always establish quite early in my classes that I have no reservations about showing students the door for lesser infractions than you're dealing with; moreover, it's become somewhat of a game in my classes. As soon as there is any disruptive behavior, my students begin anticipating my reaction, and when I finally respond by pointing to the door and to the student at fault there is a chorus of "bye-bye." Noone wants to be on the receiving end of the "bye-bye." In Asia, even children know about losing face.

However, it seems that your classes have reached the point of no return. It's too late to establish discipline and, as I said, they're probably a bunch of spoiled little rich kids anyway. So, my advice is skeedaddle on outta there.