She doesn't need to explain herself one iota.
We know enough about her to see there's plenty of issues that could've been there to crush her.
But oftentimes with such a dominant athlete like her the simple fact that the expectations are so high & that she's simply not at her peak anymore — those realities gotta be crushing enough.
She very well may have debated whether or not she was gonna even compete again. Which she may not even had much of an option on — given how badly our team needed her out there.