Daphnes are notoriously difficult to get going. You should wait and see if it really is dead. You could scratch off some bark from the biggest branch and see what colour the wood is underneath. If it's brown, I'm afraid it's likely to be dead.

I your Daphne gives up the ghost, why not invest in Daphne odora, buy a small one in springtime, and see how it goes? My local nursery/garden centre has stopped selling Daphne mezereum rubra, as the customers' results have been disappointing. West facing would also be an advantage, so avoiding morning sun.

Hi Spritzhenry and Jimmytheone,
Many thanks for taking the time to answer my concern. I actually feel a bit better after hearing you both comment on Daphne's difficulties. Roll on next year.

I agree with Jimmytheone - I have a Daphne odora 'Aureomarginata' and it's a very reliable shrub. It may not have the 'wow' factor of D. mezerereum, but it flowers in late winter and has a really good fragrance.