Answer:
Ch side by side, you are inside.
Once you know it exists, it no longer exists. What is it?
Brings you May flowers
What cleans as it gets dirty only to get clean the more you use it?
There is one in every corner and two in every room.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.