Queen Takes Darkness Book 1 by Joely Sue Burkhart

Chained in eternal darkness. Kidnapped by a primordial evil. Freeing this vampire queen will unlock hell itself.

Helayna Ironheart doesn't know where she is, or how long she's been trapped in the darkness. She only knows pain and horror when her captor feeds on her suffering. Her only hope is to access her power as an Aima vampire queen. But how can she call her guardian Blood, when she's trapped in an alternative dimension at the bottom of the world tree?

Only Darkness lives here.

So that's exactly what she must take.