Quotes from Canadian Running article on her departure. Tl;Dr, not just a mental health thing.
-------
She added that there is general confusion around what an athlete who is serving a competition ban is allowed to do vis à vis training. Given the lack of clarity surrounding the rules, DeBues-Stafford says she has concerns about operating in what she refers to as “the grey area.”
She adds that while the BTC staff and Houlihan’s lawyers have spent a lot of time and energy clarifying what she can and cannot do during her period of ineligibility, none of the other athletes have been given access to this information. “This absence of this clarity surrounding the boundaries between BTC and a banned athlete is the critical reason for my departure,” says DeBues-Stafford. “I need to know 100 per cent, black and white, word for word, all codes and guidelines that might be relevant to me or anyone associated with me in a professional capacity in this sport.”
----