I am a soldier. I am a killing machine. My job is to protect you and you, me. I have fought many battles with you. We took down countless enemies. I wouldn't be here if it wasn't for you.
You kept me sane and human, or what's left of a human. I said I would help you, save you. My promises are never broken. I proved that time and time again.
So what makes this so different then my other promises? I didn't know. I am a Spartan and Spartans keep their words. I did my best and I have failed. After all that, you are gone.
The voice in my head is silent. I failed you Cortana. I'm sorry.