Concentrating on the good doesn't mean denying the existence of the bad. It means to put the good at the center, in this case of my life, finding in my family, my faith and my hobbies the strength to look calmly at the bad, which are at the periphery of my life but still exist and are always present in my consciousness.
an argument that the people who despair are to blame for the world's problems
That's not what I said. But the people in power want us despaired, because they want us docile.