I think someone else already said it, but I resent your GF's implication that none of us on AD have what she considers to be "real relationships". I've gotten to see my wife for 2 out of the last 14 months, but our relationship is more "real" than a majority of folks out there. The quality of the relationship has more to do with the people in it than anything else.
What's my point? If it's going to work, it'll work whether you go to UPT or not. So, don't use this thing with your girl as an excuse to give up before you even get started. If the AF life is for you, it's part of who you are and if she doesn't like that part of you, then it's only a matter of time. If it's not for you, then good riddance.