Why didn't Jack sit with Auggie for lunch on the first day of school? Must us text evidence for your answer.

From the text:

So when I saw him going into the cafeteria ahead of me, I knew he'd have no one to sit with, but I just couldn't bring myself to sit with him. I had been hanging out with him all morning long because we had so many classes together, and I guess I was just kind of wanting a little normal time to chill with other kids. So when I saw him move to a table on the other side of the lunch counter, I purposely found a table as far away from there as I could find.