Dragon Kin: Blood Dragon #6 (Vampire Dragon Shifter Romance) - Blood Dragon, #6

All roads and adventures have led Sarah and her paranormal friends to this point. They must make their first and final confrontation against Michael, the champion of a deep darkness that threatens to consume the entire world in its evil embrace. Their victory depends on them finding the last of the pieces of the relic, but their best plans go awry when they instead lose one. The betrayal cuts deep into their unity and leaves them with a traitor in their midst that they're unwilling to cast aside.
They must now balance their shaky chance at victory with their desire to protect each other from themselves and the outside influences of the evil undead. All the while Sarah is slipping closer and closer to becoming a full vampire. Each night brings her nearer her inevitable destiny, but sometimes the journey is more important than the destination. For Sarah, she's determined to make sure that the journey will be victory for her friends, even if it means sacrificing herself to do it.