Not often i use the Sun as a link but this was the best article I could find - so sad. Imagine being a Stanford graduate student, World Champion 3 times and Olympic medallist and still you feel unable to continue. Much sadness and sympathy to her parents and family and friends, she seems like she was a person who would have shone in life (he had already shone) and just struggled to cope.
I feel immense sympathy for her family and friends and their terrible loss. Many people who reach advanced post-graduate education are driven by fear of failure driving them on, often sport is a fabulous outlet particularly if you are prone to depression. Catlins level of achievement both academic and physical brings with it an element of psychopathology, the drive to succeed or perhaps not to fail must have been immense. If both facets of your life become a stress rather than just one, the other a pleasant distraction you could see how her mental state might deteriorate.
There is a piece in the Stanford Daily about her death which quotes her journal published in Velo... essentially its about continuing her cycling whilst doing her post graduate studies in maths and computational engineering. She talks about knowing ones own weaknesses and looking for/asking for help ... she also describes how cyclists are built to suffer and not complain.
Palo Alto schools have struggled over the last decade with high suicide rates at both Gunn and Paly High, the parents often have post graduate degrees, about 20 kids a year get into Stanford and three quarters go to Cal from Gunn, the definition of success although all right for some is massively distorted for others.