Why don't parents understand Trichhotillomania??

So, I have this habit of pulling and ripping my hair out of scalp when I am studying and reading. I have tried to tell my mom that I am not doing it knowingly but she just doesn't understand. According to her how will someone not know that they are pulling their hair. When i try to make her understabd she thinks I am fighting with her and dhe just goes fine become bald. It is not like It is ny hair and my Papa throws in one of his "Why do you even bother with her. She is fight with you even if you say something for her good" .They just don't understand that I don't want to do this. I don't enjoy being mocked and asked again again that what happend to my hair. I am ashamed enough when I am going out trying out hairstyle so, it doesn't look weird. But they just don't understand.

Whenever I try make them understand That this isn't something I want to do , it just happens , my parents get frustrated. Recently my cousin( I love her btw, she is my fav cousin) came over and She was like what have you done to your hair. I was ashamed So, i didn't really say anything but My proceeds to rant how I am myself plucking my hair out. She then proceeds to say me to not do this like I want to do this. Whenever I go to cut my hair, the hair stylist will ask about my uneven growing hair and bald spots and mom will proceed to embarrass me I am not already enough humiliated.

Like I love my parents. They are the best parents ever but this one thing they just don't understand.