Answer:
I am a portal to another world which you cannot enter. Only you can see me but I can't see you.
I am brown and sticky
I am rubber you can eat!
If you lose one of me, you are upset, bewildered, and perplexed. If you lose two of me, you are blissfully unaware. What am I?
The more there is the less you see.
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?