"How are you?" in this situation is a greeting, not a question! It's an acknowledgement of the other, usually an acquaintance, not an intimate.

We can only control our actions, not our thoughts or feelings. Yes, we can influence our thoughts and feelings, but it is what we "do" with our thoughts and feelings that is most important, not that they exist.

No one "fakes" that they are not depressed; they just act, positively instead of negatively. If you break an arm and it's in a cast and people then ask, "How's the arm?" most likely you will reply, "It's doing fine" because it is; it is healing and you are hopeful it will heal well.

As Dusty9838 says, acting depressed, going home from work early and/or staying in bed does not help anything and actually perpetuates one's problems because of the habits one gets into.

Performing healthy acts; smiling, exercising, eating well, can help with healing depression. One may not feel like smiling or exercising but do it because it is good for one and will help one feel better.

There is nothing wrong with feeling one way but acting in a way consistent with how one would like to feel (having economic problems but helping others who might be less well off economically, for example); the actions can make us feel better.

http://scienceblogs.com/cognitivedai...l_better_w.php

http://www.psychologytoday.com/blog/...il-you-make-it