The world looks so unfamiliar to me

Everything seems so foreign to me these days. I don't understand the world I'm living in. My entire environment has changed, I don't recognise it. Of course I know all the streets, all the buildings, my room so well. Yet somehow it all looks different to me.

Imagine that one day aliens came to the earth. They came to live with us, walk amongst us, big green men from Mars with antennae on the head and black eyes. When you walked down the street they would be there, when you were shopping they would be there, when you went to sleep one would sit in the corner staring at you. You too would feel like you didn't know the world you lived in anymore. That the streets looked weird to you, the whole world just had a different feel to it, a different atmosphere. Like you saw the world for the first time.

Now imagine your boss or teacher came to you and said: "read these articles and write me a summary by the end of the day" and you protested: "but what about the alien sitting next to me, staring and hissing at me and poking my shoulder, how am I supposed to be able to concentrate while it's there" and you got the answer: "try to disregard it for a while, try to concentrate on your work and forget about the aliens."
And when you complained about how the aliens were tearing your room apart and preventing you from sleeping and sometimes kicking you in the stomach, people just said: "try to do something nice for yourself an afternoon to forget about them".
You'd want to scream too.

Now finally, imagine this only happened to you. No-one else were bothered by the aliens, maybe they didn't see them, maybe the aliens just didn't go to anybody else's houses or work etc. All other people just lived their normal everyday lives. They would respect how hard it was for you to live with the aliens tearing your life apart and scaring the living crap out of you, but they wouldn't really understand, cause no-one can imagine what it's like to have an alien sitting in the corner of your room with evil eyes, before one is actually doing it. They wouldn't understand how suddenly the whole world looked different to you, cause to them it all looked the same as always.
All they could do was to keep saying: "try to think about something else"