It sounds like from your post - you fit the classic female athlete triad. You absolutely need to work with someone in diet; you may need to have a professional running analysis (I would recommend by a highly trained physical therapist); you may want to look into a professional bike fit (again potentially by a Physical therapist who understands your injury past); And you may want to have a strength routine designed by a physical therapist rather than a personal trainer.
Not trying to be harsh, but realistic. There were likely signs that were missed. having a team around you that can point those out is important.
Good luck in 2016.
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