Friends...maybe more..please help!!!

About 2yrs ago I met this guy and at the time he was married but we would talk and nothing more. Recently we ran into each other again and he told me had been divorced for a while now we've gone on a few dates and had some foreplay. He is aware that I leave for the military in less than 3months I've had such a great time just having someone that can relate but I'm afraid that if we have sex it'll ruin it and I lose a friend that's helped me with the military. I'm so confused! Please help idk whT to do