I'm a murderer
Why did you kill?
I figured she would get a new life if I killed her.
OK, first of it's really wrong to kill anyone. They don't come back to life, and you end all that they are. You need to turn yourself in and probably get some psychiatric help.
I didn't intend to kill her, and these people think they can do anything they want and not get in trouble.
I still don't know who this is that you killed, and why you chose to do so, but it is vitally important that you turn yourself in right away, as this is a serious crime.  Unless, of course, you were just talking about a video game character.  I hope that you can clarify this for me, and then we can discuss your next steps.