Yours is a very common situation. As someone that experienced what you are currently experiencing, i would only mention it once to them which you did, and i see they told you “dont try acting holy” – but just go ahead and do that, and dont cut yourself off from your parents. Talk to them and communicate with them as you would if they were not speaking loshon horah. We have a commandment of Kibud Ov Ve’aim and its important you dont cut yourself away from them. I think if they see what a good person you are and are trying to be, they will respect you for that.
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