What do I say to my friend

my best friend 17f (whom I’ve been close with all of my life) reposts videos about how I’m not a good friend
,but acts normal when we talk. (I think reposting to communicate your feelings is silly but I digress). Growing up was hard for her as she is adopted, has a prosthetic leg and lives in a toxic household. I have so much empathy for her and I understand why she is constantly so sad and why she thinks badly of every situation but I can’t keep being treated like this. I found out she called me a bitch which, was baffling because we’ve never argued. once I said something somehow I ended up being the one to apologize it makes me feel so stupid

She introduced me to her other friend in 6th grade and unsurprisingly we became friends. Trio friendships can be rocky but I have never seen it as a competition and she does. When I hangout with the mutual friend, she stops talking to me and starts reposting targeted vids but never talks to me about how she feels . I know that’s hard for her to do but it feels like I’m just being bossed around by her because I’m afraid of confrontation.I don’t know how she expects me to feel after seeing the vids she reposts about me.

Again her sadness if valid, her parents use her as a trophy and it’s hard to watch someone go through that for years. I just feel like she takes it out on me. I don’t want to stop being friends with her I just want to be normal again. I just don’t know what to do to help the situation because it’s just gonna end up with me apologizing and her not changing.