Explain what nick means when he says suddenly i guessed the truth?

When Nick says "suddenly I guessed the truth," he is expressing a moment of realization or insight about a situation or person, often tied to a deeper understanding of motives or hidden aspects. This phrase suggests that he has connected the dots and uncovered a reality that was previously obscured or misunderstood. It highlights a turning point in his perception, indicating that he has moved from confusion or ignorance to clarity.