how I ghosted my friend...

hi i'm an upcoming hs junior in the fall and i've been having issues with this girl, let's call her Zoe. to begin, me and Zoe met around freshman yr and have been good friends throughout hs. before any issues came up between us, I had been knowing zoe has some mental issues. she's very insecure and has a lot of social anxiety, so it's really hard for her to make friends and have any confidence. regardless of this, I never saw this as a deterrent in our relationship, and I tried to ignore this side of her. another thing is that she was very clingy with me, and saw me as her best friend. she would spam me with messages in the morning to meet up, have me walk her to every class of hers, and just was too clingy. beginning sophomore yr, I had noticed a change in her personality. she became very passive aggressive with me, and would make comments that showed her secret animosity towards me. one thing about her to know is that her mom can be mean towards her, making messed up comments about her appearance, grades, talent, etc., which made her feel even more insecure about herself. the worst part about it is her mom constantly talks me up in front of her, calling me pretty, smart, etc., and just always comparing us. at first, I thought it was just her mom being flattering, but the more I interacted with the mom, the more mean the comments would get towards her own daughter, and the more uncomfortable I got around them both. as this continued, the girl became more angry with me, like giving me dirty looks whenever I talked about school, grades... or if someone complimented me, she would remain silent. also happening around the same time was the introduction of a new friend, let's call her Stacy. Stacy was never super rude or anything, but we never really clicked, yk. she too has made off-putting remarks about my grades and whatnot, but at the time they never really bothered me. at some point, Zoe and Stacy became really close, which was a relief for me because it made her a little less clingy with me. however, soon Zoe and Stacy would completely ignore mostly me, but other ppl in the friend group. like if I spoke to them in the morning they would completely ignore what I said and just talk to each other like I wasn't even there. they were also both just very self-centered... I try my best to ask my friends about their lives so they don't feel ignored, and the feeling was not reciprocated... they did NOT gaf. anyways, at some point towards the end of the yr, I began to distance myself from them, which seemed to upset them, especially Zoe. now, it's halfway thru summer, and I haven't texted either of them since school ended. since then, Zoe has reposted constantly about it, with videos like "I hate that ho" or "I wish my bsf considered me her bsf" and stuff like that. the thing is, I don't want the end of our friendship to be sour, I still wanna say hi to her in the hallway and stuff, I just don't want to be her close friend anymore, but Zoe's not that kind of person: if you aren't her friend, you're her enemy. atp I cut my losses and am relieved this is coming to an end. so I'm asking, is ghosting her a bad thing, or just me protecting my peace? and any advice for seeing her come august? feel free to respond with questions