Although manic depression is a well known psychological illness a lot of people not classified as manic depressive anyway suffer from manic and depressive phases in their life.
The reason: Expectations and wishes
Expectations are the motivation for a lot of actions you wouldn't do without the result you hoped for. You delay happiness until a specific goal has been reached. When you have success or simply too many things worked in the past you are mislead to higher goals and higher expectations. When reality tears you back to earth you fall into depressive phase because you did a lot of things "for nothing". You didn't got honored, you didn't earned the expected amount of money or some other outcome of your work turns out to be useless.
The solution: Drop your expectations
Dropping expectations initially sounds like dropping any motivation for getting to action and is pure negativism. But take a second view. When you drop your expectations
- everything that works or results in a positive feeling it is a pure wonder,
- when you do something you do it out of the current necessity or benefit without having to fear investment loss (because you simple do not invest - at least long term),
- you can also drop a lot of fears in form of negative expectations.
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