Any advice on what’s wrong with me?

So basically I have bad anxiety. It happens ever where, every single day. The last few days/ week I have been feeling super sick like not my body but in my head almost. So basically when I’m in the shower or changing I feel like someone is watching me through a camera so I just cover my body because my mind tricks me into thinking that. I cannot ride in the car without an anxiety attack. The only time I feel calmer is when I ride horses. I don’t have any friends really and I was hurt by my so called “best friend” in 3rd grade because she got touchy with me in places she shouldn’t have been. My teacher found out and told my parents and stuff. Again in 6th grade when middle school started she would talk to me and being the nice person I am I talked to her back. We would FaceTime everyday for at least 8 hours a day. She would make me do her homework for her and in the summer stay up with her until 4 am. The friendship was super unhealthy but I never realized as I was younger. So in 8th grade she blackmailed me because I switched to a private school to avoid her but ended up going back to school because of my anxiety. She made lies and hurt me. Now I’m a mess. And I also don’t have any problems in my life like no family fighting or anything