Perhaps her behavior has became more and more annoying to you and now you just can't stand it. Not to mention, people change and friendships do as well - especially when you're on high school. I agree about it letting fade with time..

Yes I agree fading out seems kindest.

Tbh many friendships fade around this time as we grow and change - hopefully new people will come into your life and hers.

hi there
i am having similar issues, in my case the friendship has been almost 20 years, but i am at different stage in my life now, she keeps texting me saying " i have not heard from you" or " call me sometime and try to keep in touch".... i am trying to come up with a gentle way to let her know that i just don't feel our friendship is the same anymore, she can be controlling, and if you try to voice your opinion she tries to shoot it down

anyways i better do it sooner than later, because i have been basically feeling like this for a couple of years now.
i don't want to hurt her feelings but at the same time i feel like i am leaving her hanging, by not texting or calling her as much as she would like.
so your not alone, you got do what your heart or gut instinct tells you.

take care