Discovering a Sibling's Hidden Struggles and Seeking Guidance

Assalamu alaikum, everyone. I recently learned something heavy about my younger brother-he's dealing with same-sex attractions. This came to light when a friend contacted me, worried because my brother was posting distressing things online about self-harm due to severe stress, past roommate issues, and psychosis he's denying. We've tried to help before, but he lives far away and has been very hard to reach. Honestly, my family and I don't talk to him much because he's so sensitive; it feels like walking on eggshells, so we avoid contact to keep the peace. Does this make me accountable before Allah? Looking through his social media today, I saw he's been leading a double life-not only this but also posting about being HIV positive, astagfirullah. My parents would be devastated if they knew, and Islamically, I'm unsure what to do. Should I keep this private? Just make dua to Allah? I'm under immense stress over it. I'm already handling another sibling who's mentally unwell and in treatment. My mom is very religious, and I'm practicing too. Suddenly, everything feels like it's crumbling. Please make dua for me and share any advice you have.