Show us a picture, please? Usually when I think I've killed something I hide it out in the garden somewhere, "the garden hospice" and come back 6 months later to find it thriving and putting up new growth. Or completely gone.
Thinking maybe the dividing was what did the damage for you. They are a plant that grows pretty slowly into a nice clump, but puts out new 'pups' at the base that you can *sometimes* propagate from. The reason they're so expensive to buy is because they're not easy to divide and propagate that way.
