Why was Ramanujan so stubborn in studying math only?

He would badly fail all the courses except for math alone. In math he would be at the top most level and best in the entire college. However, all other subjects like english, social sciences, literature, etc etc he would fail miserably. The school booted him out as a result. He then told his father, "my math studying does not seem to end and so i get no time for other courses". But if he was only studying math and no other course, then he really was not getting any real education. Also after being dropped out, he lost the chance to learn at math at college, and had to study math and create formulas on his own. His father then begged the college to give him one more chance and he assured that this time Ramanujan would pass all courses. But even after getting second chance in college, Ramanujan still failed miserably all other courses except for math. And again he said the same argument that math consumes all his energies and he has nothing left for other courses. Then his relationship got very bad with his father and as a result his father disowned him and Ramanujan had to run away from house and live elsewhere. However, even then he would not do anything but keep studying more and more math. At this stage it was clear, he wouldn't be getting any college credit and he is just studying math home for no reason or cause. Later his father got him forcibly married. The marriage did not go well and his wife complained that all he does is keep studying math all day long and all night long. In the end when he was very ill and in hospital, even in hospital bed he was studying math and writing more and more formulas and theorems. That is when he knows death is just around the corner. He never gave up his stubborn study of math until he died. So why did he ignore the rest of his whole life for exploring math only? was he a mad man?