first of all, its really baffling to me that in this day in age, guys can spent long periods of time from their significant other and actually expect things to be groovy while they're gone. i mean, the naivety is mindboggling.
aside from that. to the thread starter. if ur gonna fucck another dude's girl, a soldier/army guy is not the person u wanna fucck with. these people, especially those who are on the battle field, are already screwed up mentally. and when he gets home and finds out what she's been doing, it wont be too much of a leap for him to light ur ass up.