We all hear at some time these words " you look always so happy " and your like, "yeah..". What it means in reality is that he / she is faking everything . Well of curse someone will fake sadness, broken hearts , fears, or loneliness , is out nature to do so, I did it , you did it , everyone is doing it at some time:). Well yeah if you can't change something if you let your feelings outside you pretend to smile, congratulations .
Why do we do the same mistake, well i have an answer for that , but this is only my answer , because we don't want to worry our friends or family, or because we don't think they will understand, but if you really want to help them then , figure it out what that fake smile means:)