Could my boyfriend have tuberculosis and am I at risk?

My boyfriend has been having a cough for months now. He also has a mild pain in his lungs sometimes. He gets fatigued easily and is a bit underweight. Recently he's been having a fever frequently, although that could just be a common cold or weakened immune system. He got his lungs x-rayed some months ago and the results said there's nothing wrong with him. His regular doctor didn't know either. He was put on hold for military duty as well because of his lungs and low weight. Soon he should have a pulmonology doctor appointment, but if he could really have tuberculosis (because most of the symptoms suggest it), why didn't it somehow show up on the x-ray? Also, until his diagnosis, am I at risk when I spend time with him? My mom told me her mom once got tuberculosis, because a child with tuberculosis was sitting on her lap and breathing in her face. If my lad also has this, surely I'm most at risk because not only do I go near him but also kiss him and stuff? I'm so scared, most of all for him but also for myself and my loved ones as well :s