Should I trust my girlfriend when she goes overseas for the military?

My girlfriend and I have been together for 1 year and she's being shipped to basic training in 2 weeks. My friends and my mom even have warned me that she might start, and I quote the words of my friend, "whoring around"... Should I trust my girlfriend not to do anything with other guys? we're very very recently engaged... please offer some help this has kept me so anxious and so scared for such a long time it is a major concern of mine and I'm very very worried it may become a reality...help please :(