Oh no, oh no, I'm so sorry. I'm sorry for the loss of your Sandy and for the trauma you've experienced. I know its beyond difficult right now to accept that this was out of your control and not your fault, but please understand that you could not have known what would transpire that day. Sandy had never tried to do something like that, you didn't even know she could, she probably didn't know she could. What happened is absolutely awful but no one could have anticipated it. Please try to take care of yourself during this painful time. Since this event was especially traumatic, please consider seeing a therapist or a professional to work out your feelings and thoughts. Everyone here understands that this was not "just a pet" you've lost and that you're in very real pain and mourning.
When you finally feel ready, we would all love to know more about Sandy while she was here.