All of my best friends backstab me

I’ve recently moved states in 2021. I’m still adjusting to life here with school and friends as a person with anxiety. I’m November 2021, I started talking to a guy from my school on Snapchat. He’s a really affectionate person. He hugs his friends all the time. I’m not affectionate. I don’t mind hugs, but I can’t accept romantic affection whatsoever. I get panic attacks when I’m faced with anything romantic. And I knew this would happen, but I self-sabotaged myself by getting myself into this situation in the first place. I still haven’t really found my friends yet because at my school, different from my old life, everybody is friends with each other and friend groups tend to mingle. But there was one girl who I always went to. I followed her around like a sheep. I knew she was friends with the guy but it didn’t bother me because everybody at this school was friends. Him and I talked for about two weeks: he was really flirty. Wanting to sneak out of class to watch my music performance, hugging me, staying up all night texting me. My anxiety began flaring up. I couldn’t eat or sleep. I was worried for myself. I heard word from a friend that he had been hanging out with his ex. I was destroyed but I fell for his excuses that they just happened to be there at the same time. On the last day of school, he was playing truth or drink with his friends. My one friend told me that someone asked him if he felt the same way about his ex as he felt about me. He drank. He didn’t answer. I cut things off. We didn’t speak over the Christmas break. I was having major anxiety going back to school this year. Hiding in the bathrooms, always checking his location and trying to memorise his timetable so I could avoid him. I was scared he would talk to me. He ended up snapping me a few weeks ago. We’ve been texting ever since. But I noticed that him and my best friend had gotten unusually close. They were hanging out in my suburb without me. It really got to me. I was sitting with them yesterday during a free period at school when I noticed his arm subtly around her. I felt sick. So sick. I had a panic attack and hid in the bathrooms. My mum picked me up and I threw up. I feel so betrayed. And this isn’t the first time this has happened. It happened in 2019, when my best friend knowingly started dating my crush. I had gone to her for advice about whether I should make a move on him and she went ahead and dated him. And again in late 2019, another best friend of mine got with my ex. I don’t feel like I can trust anyone anymore. I don’t think she knows that I’m upset with her. This year has been hard enough on me already, and I feel so betrayed because my best friend has backstabbed me. I don’t know what to do.