In Death of a Salesman by Arthur Miller, Willy is the character to speak about having such strange thoughts, not Linda. This foreshadows the rest of the play, in which the artificial reality that Willy has been constructing for himself slowly begins to disintegrate, and we discover that Willy has few coping mechanisms for the world as it really exists.
Several disasters happen to the family simultaneously. The first is Willy losing his job, which comes as a surprise to Willy, although we can see that his job performance is at best mediocre, and that the loss of the job was inevitable. Biff, Willy's son, fails to get the loan he needed to start a business; we discover that Biff's career failure has to do with Willy bringing him up to think that studying didn't matter.
The strange thoughts turn out to be Willy's decision to commit suicide to provide insurance money for his family.