I'm sorry but being positive does NOT pay the bills. Furthurmore why should I think happy thoughts when I'm going to get shouted at all day long?

We had numerous call offs at my work and as a result it was hell for me. We had a visiting manager helping us out and she kept telling me to think positive and I refused. No, there is nothing positive about the situation and I'm not going to pretend its okay. I'm not going to smile while getting fussed at by customers due to the long wait times for drinks. I am not going to smile while working far harder than anyone should have to for these clowns. No thank you. Feel free to think positive all you want but I'm rooted in reality.