meaning of horrible dreams

Ever since i was little i've had these horrible, disgusting dreams, and in every single one i die.It's always in a familiar place such as my house, and even after my own death i see the person, or thing that killed me go back and kill anyone that's in the house.An example;One night my friends were at my house, and i fell asleep in between them. My dream started off as if someone was just observing us sleeping, but i couldn't see who or what it was. Then a man slammed open my door, and reached around my one friend to get to me then proceeded to drag me to my basement. He violently threw me into a bathtub where he began to slice my arms and legs with some sort of a knife. When there was enough of my blood in the tub, he shoved my head underneath it, as if to drown me in my own blood. I grabbed the side of the tub to try and pull myself up, but i couldn't. After I was dead he went up for my two friends.Before I saw him kill anyone else, my friend woke me up, she said that I grabbed onto her arm and woke her up, then let go and stopped breathing. I also had cuts all over me.I'm not sure what any of it means, but I have these 'dreams' every night.I've been told you're not supposed to actually be able to die in your dreams, because you'd die in real life, but i do for whatever reason.Sometimes the dreams are so bad I try to avoid sleeping.Please help tell me what these dreams could mean.