The other day my brother and I were sitting around talking how f'd up we are (mentally). We have never been happy our entire lives (We are both around 40). We have done a good job of faking it over the years. My wife was right there by us and spoke up and said "That really sucks." It was then I realized that no matter how well-intentioned she is she will never get it.
I have never known happiness. So I don't mess it or want it. It's like feeling bad for someone that is so mentally ill, like sever cases of Asperger's or other things, where they will never be able to live on their own. There's no need because what you talk about doesn't mean anything to them. People always look at it from their own perspective and never truly consider the other person's perspective.