Maid of Honor in bestfriends wedding!

Hey y’all, this may not be your typical post on here, but I am my bestfriends/cousin MOH for her wedding next fall. Me and her have always been super super closer since we were babies pretty much. Her other cousin who is also one of her bridesmaids, has never been as close with her as I have and has always disliked me since we were kids. I know she has even questioned why my cousin chose me as her MOH and why I deserve it.

I want to be a good MOH bc I love my cousin and I am there for her and no one else I don’t want any problems w anyone. I plan on treating her with respect, including her, and being nice and civil obviously but I can’t help but feel a little weird and kinda anxious about all the wedding stuff coming up knowing that’s how she feels about me.

Has anyone ever experienced this, can y’all give me any pointers on how you made it through and handled it?