This is 100 % true, at least for myself. As you grow older and experience sad and dark events in your life, you change. It's something personal and you don't want to show it. I started a few years ago to keep most of the stuff that keeps me awake at night to myself.
I keep a certain level of decorum around people I'm unfamiliar with. Then with my friends and family I'm of course a little more casual and candid. Being an introvert though, I feel most free and myself when I'm alone. Even little things like my body language changes when I'm by myself.
I learned about this during a college course on communications. The Internet may be a good example of this? I mean, I don't *think* some of you say 'ZADD' around your parent's or coworkers....We adjust ourselves depending on the appropriate situations
of course people might show slight emotional facial differences depending on the situation they're in, but it isn't a major or noticeable face change like the picture makes out.
"Face" is a metaphor for your behavior, interaction and MAYBE mannerism sis