How do I get my friend back?

So i join college. I see this beautiful girl and try to talk to her. I start chatting with her and kind of get close. I even go to college with her. I had a crush on her the moment i saw her (initially besed solely on looks but later her character) . So exams come and she starts asking me doubts. I am happy to help her even late nights whenever she needs me. So we get close. She is a very active extrovert and talks to everyone. So one day she asks me if i have ever dated someone.i say no. And she teases me with a friend in our class. When i say no she forces me to tell her that it's her that i like. She says she is out of a relationship and doesn't want to date anyone. So i decide i will wait for her . Soon we get closer friends and i enjoyed chatting with her. I am always uncomfortable talking with her in person. Idk why but it happens. So she used to hang out with our group of friends. Suddenly she changes her friends. Really suddenly moves to a different group. Then i started thinking she is ignoring me with everyone in our group. So i get really angry with my heartbroken. It started killing me inside with all the jealously seeing her with other guys. After a week or 2 i just couldn't take it anymore. I asked her why was she behaving like that. She told me no one in the grp cared except me and no one gave a fuck about her saying she had to always imitate talking and all. I told her it hurt me a lot and i told her i was still not over her. Then she told me i had 2 faces and i was different in person and in chat which was true. Next day onwards i still see her only with those guys and it keeps hurting me a lot. Day by day it gets tough for me to even see her. I thought we were close but i don't know if it was ever true. I trusted her and cared a lot about her. I never thought she ever felt like that way. Did she ever consider me as her friend ? I don't know what exactly to do now. I am still not over her and still want her. I still care about her and i still feel she doesn't really care much. Sometimes i feel i should be away completely but i don't want to lose her though i might have lost her already. We still have daily fights about why i am weird. I don't get how do i even go talk to her if she is surrounded by other people all the time. I am too afraid to lose her and want her back in my life. If not as anything but atleast a close friend. What to do ?