That's actually a great question, and as mentioned before, tactful, direct, assertive communication will become an important element in your success as an RN. Remember that patients and their families need you to support them while keeping it real. While I was in nursing school, questions regarding caring and ethical practice were part of each test. I was taught how to approach physicians when I had patient concerns. I was taught what to say and what not to say to patients and families. It gave me a good foundation.
Eventually you will feel confident in the role of being the person the patients and families turn to when things get hairy. Also, never hesitate to consult chaplain services with the patient/families' permission. Even if people aren't particularly religious, it is nice to have some support from a person who isn't throwing medical terminology at them!