You should never tell a friend to fuck off.
Mark is feeling very down after a bad performance at work.
Mark's friend wants to talk to him and cheer him up.
Mark tells his friend that he isn't feeling up to company, but appreciates the sentiment.
Mark tells his friend to go the fuck away because he isn't in the mood.
Mark's friend understands, and walks away after telling him if he needs anything call.
Mark's friend is devastated and upset, and vows not to talk to Mark again.