this is going to sound so typical girl...but i really like this guy and i have for a while and we started talking and my "best friend" started talking to him and flirting a ton and she has a boyfriend!!! i have no clue what to do :/

Seems as though your "best friend" is honestly just trying to be a bitch. If she knows you like him, and she was truely your friend, she wouldnt flirt with him. She would be happy for you, and supportive. She should be flirting with HER boyfriend. Its called a BOYFRIEND for a reason. Just talk to her, tell her to back off a little, and that it bothers you that she flirts with him. If she doesnt back off after that, she isnt your true friend.