You can't contain the forces of nature.
Tell her that she can help you get off more then

.
Just kidding, you said what you said about your schedules. She should, and she has to lighten up if she wants to have pleasing sexual relationships: it's impossible to think that someone will only ever find one single person sexually attractive and never jerk off, but
it is definitely possible to stay commited to a relationship. Hell, she probably does it too, it's human nature... She sounds a bit too conservative, if you don't mind me asking, is she religious or is from a repressive family? That may be the source of the issue.
And of course, never go all bananas on the porn, dude. Never overdo it, balance.