All this reminded me that I myself even did something similar, and I still feel bad. I hung out with a boy a lot over the summer, and when we got to school, my friends didn't like him, so I ditched him. I felt guilty over it for a long time, but then I just sort of forgot. We sort of got to be weird semi-friends, where we said we hated each other with these huge grins. Really it was a bizarre relationship.