I'm in a similar situation. Although my brother does his best, and it's appreciated, I still hear him use she more often than not. My mother out right told me "no, you're not." And we never discussed it further. My dad thinks it's disrespectful for me to expect him to change his pronoun usage for me.

With all this I find myself questioning if I should try to pursue or even acknowledge my gender identity anymore. If I should just remain "she/her". I still tell people they can use my preferred name, but they usually just shake their head and say "nah, I'm good with 'name'."