I think that your problem may have less to do with sexuality and more to do with your family. I want you to try and imagine that them out of the picture, just for a moment, and ask yourself:
Are you attracted to just boys and girls, or any person regardless of sex and gender identity?
It’s okay, whichever you choose to identify as, I want you to know that, and if you change your mind later, that’s okay too. I’m really sorry that this is setting off your anxiety, but I really want you to understand that your sexuality is not your enemy. It’s a part of you, and it’s unfair that other people aren’t willing to accept that. Anxiety is not some sort of mythical creature. It’s not some sort of euphemism for disobedience, it’s real. So is bisexuality, pansexuality, asexuality, and all of the others- and so, even if they won’t be on your side, you must be on your side.
No matter what, there will always be people who support you. Allies that you may not know you have, friends, and people who you haven’t even met yet. If there’s anything that I can do for you, please feel free to shoot me another ask. I believe you and I accept you.
Everything that you are is valid.