I feel stuck between needing support and being scared of being outed — Need some real advice?

I am 16 and a trans girl, not out to anyone.

Sorry, this is a bit long.

Lately I’ve been feeling like I really need good people in my life—people who accept me, who I can talk to, and just be myself around. I feel like maybe I’ll find that kind of support when I go to university, but right now I feel very alone.

I come from a mix of conservative and somewhat liberal family, but overall they seem more conservative. I’m not sure if they would accept me or not, which makes everything harder.

I was thinking about telling my cousin elder sister because I felt like she might understand. She’s well educated and studying law, so I thought she could be open-minded.

But recently I noticed things that made me doubt that.

For example, when she got a love letter in college or got proposed to, she told everything to her parents—which is fine. But even small things, like buying a sleeveless top, led to her being scolded by her mother on a video call, even though she lives 1500 km away.

There have been many situations where it feels like her actions and decisions are heavily controlled by her mother. My mom even praises her for “listening” to her mother and says that’s what love looks like. But to me, it feels more like control than understanding.

Now I feel like if I tell her about being trans, there’s a risk she might tell her parents too. And I really don’t want anyone else in my family to know right now.

Also, her mother (my tai ji) tends to share things she hears with her friends. So if this somehow reaches her, I’m scared it could spread and turn into a really bad situation for me.

So now I feel stuck. I want someone in my life I can trust and open up to, but I’m scared of being outed without my consent.

Has anyone been in a similar situation? How do you decide if someone is safe to come out to?

TL;DR: I’m a 16-year-old closeted trans girl. I wanted to come out to my cousin sister, but I’m scared she might tell her parents, and her mom tends to spread personal things. I don’t feel safe being outed and don’t know what to do.