Dormant Heather?

This is the heather plant that I bought this spring. It was so pretty, with white flowers. I kept it watered, and I've read that heather likes full sun, so I made sure it was in the sun most of the day. Unfortunately, I wasn't able to plant it right away, so by the time I got to put it in the ground, it looked like this: So, my question is: does heather go dormant after it flowers, or is this thing dead?