I've nc for this because it would probably out me.
I legally changed my name by deed poll 6 years ago, when I was 19. It was a very difficult to pronounce and spell unusual Welsh name. It's also a painful reminder of my very unhappy childhood years which were filled with anxiety, feelings of shame and humiliation due to severe social anxiety and undiagnosed autism. My name was just another thing that made me feel different and feel like an outsider.
My father is very black and white about things, possibly on the spectrum himself and has been very unsupportive about my name change. I just sent him a picture of my degree certificate - which I worked really hard for (it has may legal changed name on it). He told me that it was basically forgery because I'm X and always have been and always will be X. I've explained to him how it makes me feel but he said it's disrespectful and a slap in the face because he chose that name.
My mother and stepdad are also very black and white about things, and also refuse to call me by my current name. None of my family call me by my new name. The only people that call me my preferred name are doctors etc.
I don't have anybody else due to many years of MH issues and it all just makes me feel powerless. When my mum introduces me to one of her friends, she introduces me by my old name and I wince when I hear it, all of those feelings of humiliation and shame come flooding back and i'm just reminded that I'll always be known and remembered as X, the socially awkward child/teen/young adult.
I honestly don't know what to do. Family have been begging me to change it back but I don't want to. I like it and I feel proud of my new (ish!) name.