What did i do wrong??

Salt licks are fine, the last be sounds disgusting... But that's death for you? I'm sorry about your death, she died because of diarrhea, its fatal. If you knew, why didn't you take her too the vets? You should have at least researched to try and cure it, it's really simple. It's as simple as giving her some raspberry leaves and some burnt toast. That would have saved her life, but she's gone forever now.