Used to describe persons who don't notice anything that could dampen their spirits, and tend not to be able to remember times that they were sad or events that happened in their lives that might have been difficult or frustrating.
That's me.
Of course I get stressed out over homework and exam seasons, I cry over silly things, I get frustrated with people and things, and very occasionally, I get mad.
But generally, I'm a very happy person because I'm not thinking of any of that. When you ask me "what's something difficult that you've been through in your life?", I can't think of anything until I'm actually in a difficult situation. Then the ball starts rolling and aaaall the memories come rushing in.
But I'm easily distracted, so I can forget again.
So I live a stupidly happy life.
In other words, I'm just really good at not thinking about the bad stuff. But that's not a bad thing, right?