As he hides, Henry tries to avoid thinking about how hungry he is by thinking about Catherine, but thinking about her without being able to see her makes him feel as if he is going crazy. He decides that he has no more obligation to the Italian army that tried to kill him, and that the war is none of his business anymore. All he wants to do is "eat and drink and sleep with Catherine."
Thoughts of Catherine allow Henry to escape the forces of the outside world, including even hunger. He explicitly decides to cut his ties to the war. The one thing he wants is to escape the war and the rest of the world by focusing solely on his love for Catherine.