Mental Ailment

During our orientation, we had a talk about the mental stress people go through while at ISB. Most of the people who join ISB have been toppers in the past in their various fields/colleges/schools (and obviously they're not talking about people like me). By law of nature, there can be only one first and then the rest fall in place accordingly. So, a lot of people undergo a lot of trauma suddenly finding themselves at the bottom of the class. What they don't realize is that they're at the bottom of the pile among the cream. And suddenly, when they're in unfamiliar territory (to which there is a social stigma attached), they start to panic and become mentally imbalanced. ISB has a couple of inhouse psychiatrists to help us students out in such cases. We were all adviced to make use of their services even if we start feeling the pinch of such nerves.
My first reaction to it was to think who'd be crazy enough to go to a shrink n stuff. Then one of the people in the administration said something that got me thinking. She asked us why going to a doctor for physical ailments was considered okay by everone, but going to one for mental ailments was not okay. If someone has fever, or a bad cold we take them to a doctor without hesitation. Why don't we do the same when someone is mentally ill as well? Why is there a stigma attached to going to a doctor for medicine/advice on such types of illness alone? It's also another ailment and may sometimes need professional advice?