What am I...

“Blood thirsty monsters everywhere even inside of you! You can’t run away from me my dear I will eventually consume every part of your body,” a voice hissed inside of my head.
“When the time comes I will become one with you whether you like it or not you are a monster in your heart. You are more moroi than everyone thinks even you know deep down you are.”
“What am I…? I can’t be a monster! No, this cannot be! I am not who they say I am I know I’m not really…or do I know?” I ask in utter confusion.
“Remember darling confusion and innocence is a sin.” Laughter erupted through my head.
“NO! I am no monster! I refuse to believe such lies I will never become who you say I am. Even if I am a moroi I will not feed off the blood from others,” I screamed at the voice, I was getting pissed now.
“But you already are a monster. You are me deep inside. You can’t run away from the lust for blood that you will soon begin to experience once you turn 16 and get your fangs. It is inevitable.” More laughter drenched in the sound of evil erupted through every part of my mind eradicating everything else in its path.
“Yes I am a monster.”

What am I...
Love triangle, supernatural, action.