I am generally a happy smiley person but I also strongly dislike being told to smile by strangers. I remember right after my father died it was all I could do to go out in public and not sob my heart out. Some stranger said "smile, it's not that bad" and I was like "oh, really?". Another time my boss told me that my chipper nature was a great morale booster so was relying on me to maintain that while the company went through a hard time. I was a bit offended because my moods are actually genuine, not put on for his benefit and not something I owed him or that he paid me wages for. I'll smile if I feel like it which thankfully is a lot of the time.