Parents told my partner not to be with me

I always thought my parents were supportive, they struggled with names and pronouns at the beginning but you can really tell they’ve tried hard, they introduce me as my new name, they come to appointments about my surgery, they ask me about my hormones, take an interest basically (I’ve been out and T for over 2 years now).

Anyway, I recently found out that about a month ago, my dad spoke to my girlfriend of 8 months and said that I will never be a boy, I’ll always be a girl, that she doesn’t have to be with me and it would be better if she wasn’t.

My girlfriend held back on telling me this as she didn’t want to upset me, she isn’t going anywhere but is struggling to have a relationship with my parents as she can’t accept their views on me.

Obviously this has been a big shock to me, I thought they were supportive but clearly they’re not - is it worth bringing this up with my folks or should I just accept it.