Good Luck. The advice above sounds good to me. I suggest that you hang in there if it's only going to be a month before you see her again. If you still have the urge you should definately express it to her and ask her if there's anything she sees in the relationship that needs talking over. The urge to cheat can sometimes be an indicator of a problem but it is very common in long distance relationships. My first thought when reading your post though was indulge in as much phone sex as you can and I loved jay-g's cam idea. Camming is great, and fairly satisfying (though I am speaking from a woman's point of view). Stay away from temptation as much as possible and hang in there. It will be worth it not to endure the guilt and possible break up if you really value your relationship with your girl. I wish you the best of luck and all the strength you can muster.
__________________
"Always learn the rules so that you can break them properly." Dalai Lama
My Karma just ran over your Dogma.