Collusion is probably the most common problem in early stages of disease diagnosis.
Don't feel too frustrated. The dynamics of families change and often very strong emotions are released around the point of diagnosis. This situation may occur as a specific request from the relatives to you not to talk to the patient about changes in their health status. It may occur as a specific request from the patient to you not to talk with their family or significant others about changes in their health status. The patient, on the other hand, may merely avoid acknowledging the situation to their family.