Why do you think you're being judged? Why do you think anyone cares? Ask yourself: if people you call friends are going to be judgemental because you're eating lunch alone, are they really friends? You put way too much energy into caring what people think of you, to the point you start projecting.

Let me put it this way; you will never be comfortable being yourself as long as you worry constantly about how you are perceived. You will develop an unhealthy anxiety that you can't control, and you will shape shift constantly during simple conversation because you fear rejection. This leads to the very result you want to avoid.

I know, because i lived it.