It is hurtful to stop talking to someone entirely.
Jack recently found out that his brother Murray cannot pay back all the money he owes Jack.
Jack wants to react to the bad news.
Jack tells Murray that he can take longer if he needs to and that he understands times are tough.
Jack tells Murray that he can forget the loan but that he'll never speak to Murray, ever again.
Murray is relieved Jack isn't pressuring him for the money and is giving him more time.
Murray is deeply hurt that his brother is cutting him off over money and very sad about it.