Candy wants to know if the
dream will become true.
The quotation on p.
70 refers to their dream. They want to have a farm of their own. Maybe
now this dream is destroyed because Lennie killed Curley's wife, and Candy
discovers her death. But Candy doesn't want to give up hope of living
with Lennie and George, and of having a garden of his own. However, the
farmhands want to catch Lennie and kill him.
Therefore Candy is pessimistic now.