I know it's difficult but she will be absolutely fine and after it heals you won't even notice the difference
My tail tale is a bit different and hopefully will make you feel like you're not the worst owner in the world (which you aren't - her injury is just one of those things
)
My brother was clearing some scrub from his land with a scythe and his 12 month old lunatic black labrador was tearing around like a mad thing. At one stage he called her back and she tore back to him waving her tail as hard as she could....and sprayed him with blood. She must have got in the way and he accidentally amputated a couple of inches of her tail
She had not made a sound and she wasn't at all bothered and after a trip to the vet, a couple of stitches and a fetching purple bandage she was fine (and you'd never know her tail is shorter
)
Will be thinking of you and Poppy