@amist,
There are ample examples of non democratic regimes throughout history that have not resulted in widespread despair among the populous. Surely though the kind of widespread you are talking about would not take place in a sufficiently democratic government, but it's not been properly demonstrated that despair of this kind is a problem, so you've pretty much set up a false ailment, the cure for which is representative democracy.
I'd also like to point out that many people who live in representative democracies suffer from the kind of depression you're asserting would arise in the lack of at least of a representative democracy.
It also doesn't make sense to me that a government that is serving its proper function would cause distress in a population. It seems to me that this would be evidence of something wrong within the population that is being distressed by the good government rather than evidence of a need for the change of style of government.