It's what he would call a question of allegiances, and he expects you to be pretty literal about them. Not only about himself and all the things he believes in, his present and his future, but his past as well."
Look Back in Anger, 42.
In this quote, Alison attempts to explain Jimmy's character and motivations to her friend Helena. Jimmy's allegiances are a result of his intense character and desire for raw emotion. Casual acquaintances will not do for him. Such relationships lack power and realness. Jimmy expects all of those he cares about to be committed to those things as well. Alison's break with Jimmy occurs when she goes to church with Helena, a rejection of Jimmy's secularism. He takes this action very personally as an affront to him.