So we all agree that the grandfather paradox is retarded, right? If you went back in time to kill your grandfather before your parents are born, that doesn't mean you're going to magically disappear. You exist, changing the past is not going to change the fact that you - the person now in the past who murdered your grandfather - exist.

Yes, your grandfather will be dead. Your parents, and by extension you, will never be born in the present. But YOU - the living, breathing person who went back in time and killed your grandfather - exist and no amount of hypothetical paradoxes will change that.

Now, if you were to go back to the present via forward time travel after killing your grandfather, then legally you would be a person without an identity. If you went back to your childhood home during a time period in which you were growing up, there would be no you. But YOU still exist and would therefore experience a world in which you were never born.

That's it. No universe-destroying paradoxes, no people magically appearing and disappearing into thin air, just you and a world you technically don't belong in.