Depression is not always sadness. It is also feeling numb at 3am but smiling and laughing with friends at 3pm. It is also not being able to get out of bed even though you were fine the day before. It is also not eating because you are not hungry or can not be bothered, but also over eating because you are bored and feel empty. It is also loving too hard or not at all. Depression is not a constant feeling of sadness, depression can be hidden in happiness. Your depression is valid even if people say it is not just because you smile.