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In fiction and folklore, a doppelgänger is a paranormal double of a living person, typically representing evil or misfortune. In the vernacular, the word has come to refer to any double or look-alike of a person. The word also is used to describe the sensation of having glimpsed oneself in peripheral vision, in a position where there is no chance that it could have been a reflection. Doppelgängers often are perceived as a sinister form of bilocation and are regarded by some to be harbingers of bad luck.
In some traditions, a doppelgänger seen by a person's friends or relatives portends illness or danger, while seeing one's own doppelgänger is an omen of death.
For years I have been in love with someone who I cannot have and I've finally come to the conclusion that subconsciously I have been trying to fill his place with his doppelgänger. However the great problem is, that if I find his doppelgänger, then they will eventually meet. If one were to give any weight to the folklore, then my finding his doppelgänger would be an omen of illness or danger, for them to meet would be an omen of his death and I would forever lose him. If I were a superstitious person then I could say that this is the reason why I shall forever be alone- I love him and for him I wish only happiness and peace and I cannot bring illness or death upon him.
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And this is the reason why I shall forever be alone.