The speaker sounds disappointed, as he was so close to finally grasping but they keep leaving him. It also says he chases them madly but is unable to catch them. Showing disappoint in himself.
?????????!!!!??!???!????!?!??????????!?!!?!
I'm not sure what you're trying to ask, but I'm a good answerer.
Answer: He often becomes annoyed with his mother's grumbles.
Explanation: Many times throughout the excerpt the tone is that of someone not agreeing with what is being said. " I was supposed to have it all, and in her mind that meant a nice quiet suburban town in California" This is meant as a "disagreement" but not necessarily that of importance enough for confrontation.
George shoots Lennie and their dream is over, their plans have all came to nothing, just as the mouse's did