Wikipedia doesn't think you don't exist. They think you aren't notable, which is why they would say you aren't notable, not that you don't exist.
There simply can't reasonably be a page about EVERYTHING:
http://www.en.wikipedia.org/wiki/WP:NOTE
In that they explain what notability is and why such a standard exists. Also, if you aren't notable enough to have a verifiable source written about you then it's original research:
http://www.en.wikipedia.org/wiki/WP:NOR
which is a no-no for an encyclopedia.
Slashdot Mirror
This is what is known as asking for meatpuppets: http://en.wikipedia.org/wiki/Wikipedia:Meatpuppet#Meatpuppets
Wikipedia doesn't think you don't exist. They think you aren't notable, which is why they would say you aren't notable, not that you don't exist. There simply can't reasonably be a page about EVERYTHING: http://www.en.wikipedia.org/wiki/WP:NOTE In that they explain what notability is and why such a standard exists. Also, if you aren't notable enough to have a verifiable source written about you then it's original research: http://www.en.wikipedia.org/wiki/WP:NOR which is a no-no for an encyclopedia.