So sorry this is happening to your DD. I've been there, I know exactly how you feel.
The first time DD was diagnosed with a stress fracture was so hard on me. I couldn't believe this was happening. I kept thinking this was a bad dream and I would wake up and she would be happily flipping at the gym. It gets easier as the time passes and you start seeing the light at the end of the tunnel.
For us though after DD healed and went back to gym the injury re-occurred and wouldn't get better. That's when I started to get used to the idea that this might be the end of gymnastics for her. It felt like the end of the world for both her and me. I didn't know if she would ever find something that she would be as passionate about as she was about gymnastics.
But guess what, there is life after gymnastics. DD did find something else that she loves. She found dance, and just as she used to want to spend every minutes of the day at the gym, now she wants to spend all her time at the dance studio. Her first dance competition is coming up in March and I'm looking forward to that. It's been two years, and I miss going to the competitions with her. I know dance competitions are different from gymnastics meets, but still something for me to look forward to.
Good luck to you! I hope your daughter is able to come back to gymnastics. Do make sure to find the underlying issue and fix it., otherwise the injury just keeps coming back.