Sometimes if challenging thoughts, voices, or behaviors is too hard, it might be better to try to look at them in less negative and more neutral ways. Is there a way to just remove the judgement? Sometimes that helps break them down and help you look at them slightly differently to make it easier to challenge later on.
I'm not entirely sure how that might work with your situation, but I guess maybe trying to see it as less who is right/wrong or lying/telling the truth look at it in a way that suggests that they are all suggesting things that they perceive to be true and they think are in your best interest. Like, thanks voices for telling me what you perceive this situation to be. I will consider that point of view. Same with your parents or psych, etc.. Thus then the choice is up to you to decide which one might really be in your best interest?
That might be a bit too abstract to make much sense.