According to Bernard, something happened to Biff when he went to Boston to find Willy after he failed to pass his math final. " ... after that I knew he had given up his life, what happened in Boston Willy ...?" What happened in Boston?

Biff went to Boston to catch up with his beloved father before his college visit. When he finds his father with another woman, he realizes that Willy is truly a fake, and does not have the great qualities which Biff had formerly believed his father held.

Explanation:

The reason Biff goes to Boston, was to to tell his father that he has failed math and will not graduate from high school. Biff was hoping that Willy will talk to his teacher and persuade the teacher to let him pass and graduate.