My girlfriend... is ignoring me?

Okay. So me and my girlfriend  see each other like on the bus and orchestra that's it. And every morning when I She gets on the bus, I smile or wave or something, and she doesn't bother to smile or wave back. And lately she doesn't bother to even look at me or talk to me. And today at lunch I was sitting right near that little hallway where you would line up, and she was lined up right next to me and didn't bother to give me a hug or just a pat on the back. In orchestra lately she walks with her friends. Which idc but she gets to see them almost all day and I wanna walk with her and ask her how her day was or hug her before I leave to class even today I took the long way to class and got in trouble so I could try and spend more time with her.  And that 'Vivian' girl calling her babe is not okay at all.  And so I go to pick her up from last academic everyday when I can, and One of my best friends comes with me and he steals her away and won't let me hug her or put my arm around her and it aggravates me!!! And even then she's still talking to her friends and there's not even room for me in the hallway!!

I'm feeling neglected and sad because I'm starting to think she likes another girl or doesn't like me anymore. Please help.