I suppose it’s your choice if you want to continue being her friend or not. Just because she’s a childhood friend it doesn’t mean you need to be friends with her forever.

Imo friends who compete with you are not really friends. Friends are supposed to support each other and not act like they are enemies.

You could try talk to get about it and tell her how her behaviour makes you feel uncomfortable and that you think she should be herself and do her own research about things. If her boyfriend is not completely into her and flirts with others that’s not your fault and as long as you don’t entertain him, it’s her call to me. She could drop him and start dating someone who likes her instead of trying to be something she’s not for him.