“Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope and happiness out of the air around them.
Get too near a Dementor and every good feeling, every happy memory will be sucked out of you. You will be left with nothing but the worst experiences of your life.” – J.K. Rowling, Harry Potter
Dementors can be a symbol of depressed feelings. As soon as those feelings hit you, they slowly suck the happiness out of you, if you allow it to. It’s necessary to equip ourselves with the right “spells”/tools to fight off these negative feelings.
In the films that tool is beautifully represented by thinking of the happiest memory you have and that will blast out of the wand and chase the dementor away. I think, to some degree, the same can be done in reality. When you feel the dark emotions beginning to come near you, think of the happiest memories you have. Write them down on paper. Recall the memory in detail. Think or write about the things and people you are grateful for in your life.
The point is to nudge yourself out of the negative spiral and loop, and with time, swim to the surface.