Melancholia, doubts and discouragement. For those people of whom we say that they wouldn’t be happy if they were happy. They fall into despondency and tend to give up at the first stumbling block. However, as soon as they overcome this negative state, they gain deep conviction. No result is a failure and no challenge or obstacle too great when they give their utmost!
Those who are easily discouraged. ... any small delay or hindrance to progress causes doubt and soon disheartens them.
"The Twelve Healers and Other Remedies"