Really need help in my relationship with my friend...?

If she's really rude then you don't have to be friends with her... Don't get me wrong still be nice to her but you don't have be her friend. If you want to be her friend try asking your mom how you should handle this situation. If she doesn't want to listen to you I guess you'll just have to stop saving her from embarrment. If she wants to be embarred then let her be embarred. Good luck. Sorry that this didn't help much.