I feel incomplete

I don't even want friends or a partner because what am I supposed to do with them? They're not going to make me happy long term, I already know that from experience.

The problem is that I feel incomplete my whole life, like I am searching for something I can't find and like I don't belong here.

I know it sounds like the most overused chliche phrase ever but since I am a child I am staring into the distance occasionally, wondering why I am even here. It feels like sometimes, or most times even, the world loses dimension and like something essential is missing. Everything is so super bland and boring, so pointless.

At times this pointlessness seems like an eternal black void that overlays simply everything and robs everything of any meaning it could have ever had.

Hard to explain. Suddenly the world is gray and flat. Like in one of those dreams where you can't walk anymore because your hips hurt in a weird way and it feels like you're walking through 1-m high wet sand.

What scares me is that sometimes I seem to jump from one extreme where everything seems justified and colorful and full of meaning to that bland space in 1 second. It's like turning from a child suddenly to a 80yr old that is weak and tired of life. What causes the shifts I don't even know.

My whole life I am searching for something that keeps the world in the colorful, meaningful state, but I can't find it. I guess it is something in myself. I also have that deep fear that everybody knows this and it is normal, and people just learn to live with it.