the way that you phrased that implies that you have never tried to enter respectful conversation. you want to kill them, and they want to kill you, and both of you know that, so natrualy neither of you trust each other, but this situation is also clearly not favorable to either of you. try make them realize that their life is more than just killing you. try to get them to think about why they want to kill you. you don't have to be friends, you just have to live with each other
it may seem like talking to them won't do anything, but you would be surprised how much talking out your issues with each other has helped people in similar situations. try to talk it out at least a few times before ruling it out.
I realize that the tulpa files weren't the cause, but I still recommend being cautious around gearheart as they have a history of doing shady stuff and currently have potentially harmful hypnosis videos on their youtube channels. remember to always listen to a hypnosis file without trancing to it first to make sure that it is safe.
it is possible to get rid of a tulpa (called dissipation). to dissipate a tulpa you mostly just ignore them. since your voice is far more difficult to ignore than a regular tulpa, you might have to actively distract yourself in order to be successful with the process. I only recommend this as a last resort though, because it is very seldom that a tulpa is entirely irredeemable.
I don't believe that there is anyone that specializes in tulpas specifically, but most therapists should still be able to offer help, and any decent therapist will be able to identify that this isn't a symptom of schizophrenia