Take it easy!
In my humble opinion, teaching in Thailand is not that harmful. Some people rather allow external factors to harm them. I believe that teachers with proper qualifications, like degrees in education and so on get paid well. For the other ones, who get paid less, the golden rules for a happy life in Thailand are always the same: Just ignore, or at least don't get too involved in all those things that make no sense to us, or that we, as foreigners, cannot change. Get a life outside the working place and surround yourself with positive people. Well... at least for me it works, and I've been here almost a decade. Peace
Roger