My best friend keeps on copying me... what should i do?

I love my best friend but she keeps on copying me. I did tumbling she did tumbling, I do cheerleading now she wants to do it, I liked this one guy then she liked him. I totally hate when people copy me. I hate even more when people copy my clothes. Like today, I wear a ROXY bikini to the beach (I surf so I LOVE Roxy) and now my best friend, who wears Justice ones, is out looking for a Roxy bikini. I know when people copy you it's a form of flattery but I don't care. It's annoying. I don't wanna hurt my friends feelings. What do I do?