TB spread with minute droplets from infected person. One TB patients infectes minimum of 8 to 15 patients in his complete life time. Even if a person is exposed to tuberculosis bacteria 85% chances that person will not develop TB infection because of his immunity. But is a person is immunocompromised meaning who's immunity is low can develop primary lung TB btw TB can also develop on skin/your gut/ genital tract especially in females so it is not always lungs that can be involved first. Out of that 15% get a clinical symptoms which most resolve with treatment but if not treated it may goes on like a chronic infection.
So if you don't develop any symptoms like cough, night sweat, weight loss or fever you are good to go.
Next Steps
Even if you are not satisfied you can get a chest x ray in 3-4weeks just to be sure. If you get it now it will be normal of course.
Ask that person to wear mask when he is around people and make sure if you can that he get treatment started asap it will be a good deed towards society.
It also doesn't mean you guys isolate him completely as it will effect him psychologically.
Take care of yourself and Him if possible.