Usually the first "break" is Labor Day weekend. I wouldn't put the ban on coming home for that weekend if the school is anything like mine--I would be the only person in the dorms when I did stay, and my school was far from a suitcase school. I guess that I should note that I never was a homebody, but I still only stayed if I could pick up some work at school to offset the $100-$200 cash that I'd make at home. The longest I went was probably early August to Thanksgiving, but it is hard to go without seeing your dog for that long.
Since she's honors everything, does she get early move in? Try to get her there as early as possible.