What do I do

I keep putting distance between me and my bff/bsf, even tho I don't want to. It's just that, sometimes I snap at her randomly (unprovoked), I don't know if I'm just taking my anger out on her or I'm slowly finding her annoying unconsciously...ik I don't tho...I consider her as one of the most closest ppl to me, I consider her as my sister almost. So idrk...I don't want to push her away but I just keep doing it with me only realizing too late ╥﹏╥