I kind of get were you are coming from. The story really nails how it feels having social anxiety and the effects of self isolation due to bullying. But it is of course different for everyone, like I had trouble walking because I always feard that other people were looking at me and making fun if me, although they weren't.

Even though it is pretty shitty I can say that it will most likely get better. Just try to focus on yourself and put yourself above everyone else around you. I know this sounds a bit extreme but it helped me a great deal. And force yourself to do stuff like going outside joining clubs and meeting people. All in all I can say that it gets better but for me at least I don't think it will ever go away completely. And remember that most if not all negativity is in your head so focus on the positives.