I work in a place with a lot of lingering people (gym) and there is one member in particular who is ALWAYS laughing/giggling/happy. She cannot go five words without laughing or giggling. It's getting to the point where nobody at work wants to talk to her or even approach her. People make sour faces when she approaches and the staff hides or pretend to be busy when she comes near. This cannot be normal. This is a form of anti-social behavior. In other words, mental illness.
At first, I was going to answer in a flippant mannerso here are two answers, one serious, one not so serious... 1 - as a man who has had his share of depression in life, people who are always happy actually get to me - not wuite to the point of offending me, but a sheer and utter inability to comprehend how they could be this way. 2 - For a serious answer...While it may seem that always being happy would be bliss.....On the flip side one could also argue that the mind feels a whole range of emotions, and if a person does not feel all those emotions, then their mind is inheritantly not operating at its fullest potential.
I believe it is wrong to assume someone you see as being "always happy," as being mentally ill. Chances are that "always happy" person, isn't always happy. People tend to put on different faces for different people and that does not make them mentally ill either, it's just a function of being social.
It's hard to make a judgment that people who are always happy are mentally ill. Each individual lives a different life than the next and it's possible to place a value on why some people feel is as they do. While it's possible that some people who are always happy do have a mental illness. It's entirely possible, too, that their life experiences have just led them to place a value on life that is consistent with constant happiness.
I do not believe that people who are always happy are mentally ill. I think its dangerous to go around labeling people a certain way based off of a few interactions. For the most part, people are not happy 100% of the time, even if they appear that way in public. Some people may be happy more often, but that does not indicate mental illness.
What a ridiculous notion! If someone has a happy disposition, or has learned to look at the bright side and appreciate the good things they do have, they are blessed. If you envy them, envy in silence and don't label them "mentally ill." I would rather say that always negative, critical grumps are mental cases than happy people.
Just because someone is always happy does not mean they are mentally ill. Some people just enjoy life and choose to be optimistic over being broody and upset about everything. I think it is good that there are people out there that can manage to be happy all the time.