Friendships are supposed to be a source of comfort, joy and support. But even in the closest relationships, communication can break down, leading to tension.

“In friendship, like in all human relationships, misunderstandings and hurt feelings are inevitable,” said Vanessa Cornell, a friendship expert and founder of the community support network NUSHU. “What really determines the strength and resilience of a friendship is how those moments are handled. One of the quickest ways to undermine healthy communication is falling into passive aggression.”

Passive aggression is basically expressing your negative feelings in ways that are not direct. Some classic passive-aggressive behaviors include not replying to texts or changing the subject in conversation to avoid acknowledging what someone said. You might flake on invitations you previously said yes to, or you might ice someone out by being less warm and excluding them from your plans.

“Giving a friend the silent treatment rather than telling her what you are upset about is passive-aggressive,” said Irene S. Levine, a clinical psychologist and friendship expert. “It is a way to upset and punish the other person. A roommate who slams doors as she goes from room to room because she is upset about her friend not assuming her share of responsibilities for cleaning up that apartment. She is acting angry without saying anything.”