I had a experience of loosing a good friend while studying; we both knew each other very well..we were from chandigarh, our ranks were adjacent; same branch..shared so much in college..
it wasn't traumatic for me i have a jolly good nature that does help. Other is belief in god.....it helps to maintain sense of calmness. Infact all of our batch remembers him every year by doing some deed; and all took it in a adjusting way. It was a important lesson.