Complications of Long-Distance Teenage Crush

I met a guy named Bilbrone at a church conference, and we connected despite living in different cities. I live in Chicago, and he is in San Jose. We kept in touch throughout July, and he was sweet and kind. My cousin Angie, who lives in LA, was visiting and insisted on meeting him through a call, which I thought was odd but went along with it. Angie quickly added him on social media, which made me uneasy. On my birthday, while I was celebrating with friends, Angie called Bilbrone without my knowledge and lied about her age. They spent the whole time texting instead of including me, which heightened my anxiety. Frustrated, I ended the call and retreated to my room, where I experienced an anxiety attack and called my best friend for support.