Girls, how to tell if someone is suffering from smiling depression?

Anonymous
I know this person that is very good at hiding her feelings. She's the type of girl that can act strong and happy on the outside, but is actually very sad on the inside. Her friend told me that she's actually very sad on the inside but she acts very happy. Sometimes I see her really talkative and happy in school but when she's alone she's just on her phone and has seem sad. Would she actually be happy or is she sad? Are there signs that I should be looking for?
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23 d
I know this person that is very good at hiding her feelings. She's the type of girl that can act strong and happy on the outside, but is actually very sad on the inside. Her friend told me that she's actually very sad on the inside but she acts very happy. Sometimes I see her really talkative and happy in school but when she's alone she's just on her phone and has seem sad. When other people talk to her she would seem happy and smile a lot but sometimes I just find her quietly working by herself
Girls, how to tell if someone is suffering from smiling depression?
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