I know you're a Navy dad, and I'm air force, but the advice is neutral to any of the academies. Things to impress upon her.
1. She is NOT the 1st, or ONLY person to be going through this. Plebes have been doing this for hundreds of years, and there are more than 1000 other plebes right next to her, going through the same exact feeling, stress, anxiety, etc... SHE IS NOT ALONE!!!
2. The academies were not meant to be easy. If they were, everyone who be doing it. It's suppose to be challenging. It's suppose to be stressful.
3. The purpose for all the screaming, is to break down your individuality. How do you take 1100+ individuals from 50 states and territories; all with different personalities; all with different backgrounds; all with different experiences... and make them perform AS A TEAM???? You break them down to the least common denominator, then you build a team from there. That's what the military is all about. Being part of a team. No one individual has ever won a war or battle. It took the entire team. You can't have all that "Unofficial Leader" psycho-babble that is formed in normal life. You need TRUE TEAMWORK.
4. All of this, is why we, the United States of America, have the best military on the planet. That's why we're the best country. And for your daughter, she can be part of something bigger than herself.
Emphasize the positive. Emphasize that there is not one feeling, emotion, action, etc... that she will have or do, that hundreds and thousands of other plebes haven't gone through themselves. Best of luck. Mike....