My 14 year old daughter is going away to boarding school in the Fall and I am having a hard time

I think it would be the same thing after she was accepted - basically what is her level of enthusiasm? Has she joined the Facebook group of accepted students? Is she jabbering on about how she is going to decorate her dorm room? Is she curious about who her roommate might turn out to be? For my D it was just a constant topic of conversation in the months leading up to September. If she is not talking about it at all then perhaps you need to re-visit the subject of her commitment to attending.