Being murdered in a dream is often symbolic. It shows that a part of your inner self has outlived its usefulness and it is time it be discarded. I have been in dreams where I have been murdered multiple times! Once you get that its a dream and nothing, really, has happened to you, you just can sit back and enjoy it like you are in some scary movie. There was a period of time where I was killed in my dreams one or more times a night for months on end. This was a period of intense inner growth. Dreams are 99.99% of the time purely symbolic. Start digging for that symbolism and you will begin to see what is outmoded within you and ready to be discarded to make room for something new that fits who you are now.