In the famous book Brave New World, there is a dialogue between the  Resident World Controller of Western Europe, Mustapha Mond and the characters Bernard Marx and Helmholtz Watson, in which Mond points outs that, when the primary goal of the government became to make people happy, one of the things that had to be sacrificed was the truth. I believe that this dialogue demonstrates a valid point against the ideia of making happyness a primary goal of a government or even of an individual.
If be happy is all that matters, what will we do with the inconvenient truths that can make us unhappy? The ability to bear the consequences of the truth, is not only important to build character, but also essential to the advance of science and technology. If we just stop when we reach the point when we can trap ourserves in an illusion, we condenm humanity to a live of futility and oblivion.
To sum up, the ability to live a meaningful life, not only facing the reality we live in, but making an effort to change it for the better, is not only an act of heroism, it is also a necessary act for the survival of what we call humanity.