You can see, it's not difficult. For example look at other people's faces. Some people, no matter what problems and suffering they are enduring, when they go out they always try to appear happy and show a positive aspect to others. But other people always go about miserable, and angry. I honestly think that it indicates a fundamental difference in the way these two kinds of people think.
Human beings are actually very simple.
Some are a disaster within and it shows on their faces and makes those whom they meet feel sick. Others, even though they are suffering intensely, always put on a brave face because they are considerate of the way others feel. I believe this is very important. It doesn't help. You should try to control your emotions, speak evenly and so forth.