Being outed

So I’m 15 and I’m bi I first came out to my youngest sister, honestly cause if she told anyone I could deny it and they’d believe me. Anyway my parents and very religious, like get in there car and the radios on “the message” and I got in an argument with my parents about something small and my father ended up saying something very transphobic so I told him off. And then my stepmom screams “we know you’ve been telling people you gay.” And I say “so what?” And she goes you don’t need to take that out on us. As if it was an emotion or something. So I knew my little sister told them and frankly I didn’t care. I was very angry and hurt. We continued to bicker and my stepmom continued to say “I don’t care that your gay, do I hate people who murder or have abortions?!” (Comparing it to some sort of sin or something.) ( not trying to start on the abortion debate either) so I yell I’m bi and she said that she doesn’t care what I call it and that was the end of it. I never had a coming out story or anything. Someone I trust outed me to the most homophobic and transphobic people I know My own parents