I'm on the verge of a breakdown!!!

I just don't fit in this world, never did. The difference is before I thought I could find a place where I'd fit in, or I could change myself to fit in. But now, after living in six states and trying every self-improvement scheme, I've realized it isn't possible. I don't even think this world is worth fighting for anymore. There are men shooting up elementary schools and parades. Why would anyone want to exist in this world?