What an honor! One to be taken seriously, on both sides of the issue. Does the Academy prevent the cadets from being married after they are enrolled (one surmises that there may have been a tradition established to take care of accidental pregnancies).
The first year of training is extremely rigorous, and not a good time to be married under any circumstances. It's at least as hard and maybe harder than a medical intern's first year, when they are up all night every third night.
These kinds of strictures are in place for a reason, to determine who can make the sacrifices necessary to lead others towards the ultimate risk.
On the other hand, if you lose out on marrying the right person, another may never come along. In the old days, people planned on waiting as much as four years for all conditions to be arranged before they married. Sometimes the girl would go and live with the boy's parents if he was in the service. A friend of mine did that and even converted from prot to catholic for her officer husband, who ultimately was killed in Vietnam. Their story was told in the film "We Were Soldiers."
Bottom line, most of today's parents have little to say about their kids' decisions after the age of 18; the ACLU has made sure of it, and wants the state to have total control from birth onwards. But you are obviously a loving parent, so you have influence. Deliver your opinions and evaluations with love, and it will help.
I believe that after completion of the first year of the Academy cadets are then given more freedoms and are allowed to marry. It is that first you, as you stated, that the rigor of the program makes being married extremely difficult. My wife and I would have no problem with this young woman coming and living with us if Robert chooses to apply for enrollment and makes it. But, the decision will be up to him and them. I can only give my advice, which I’ve done.