Do you really think so?
I'll tell you what I saw: A clingy mess and a teen boy who's scared of intimacy dating, even though they were fully incompatible, trying to force it to work with just pretty emotions and 0 realistic plans, and, the moment it inevitably went to shit, the clingy mess convinced her bf to stay with her out of pity, and I assume some fear that exactly what happened would happen, hey stayed together while the boy's mental health deteriorating from both forcing himself to date you and witnessing examples of her gf being a huge asshole to her ex and actively making her life way worse and finally letting it all out.
No offence, Hazel, I care abt you, I'm not attacking you, I've made the same mistakes, but you can't just say "He left me for someone else"