my best friend (16 f) is mad at me for distancing myself (16 m) after she got in a relationship and now she hates me

so my best friend (16 f) has been in a relationship for about a year. her boyfriend is great but him and i (16 m) aren’t really that close. we definitely tried being friends when they first got together and we’re civil. i dont really have an opinion on him, hes a great guy but we just dont have anything in common so conversation dies very quickly. anyways my best friend is furious with me as i have ‘ditched her’ and i havent been there for her in recent months. if im being honest i get where shes coming from but she wont hear my side at all. the thing is her boyfriend is very obviously uncomfortable with us being friends (im a bi male and have absolutely no interest in her). now i totally understood his distrust at the beginning and assured him there was no competition but as time went on it just started to cause arguments and issues in their relationship. he clearly thinks i like her so i decided to take a step back. i stopped asking to hang out as much as we used to and although we hung out occasionally i made sure to keep a bit of distance and id invite him along for plans although he’d never come. also id often cancel when he would get mad at her for meeting up with me because i really didnt wanna cause any problems and dont wanna be a threat in any ways. however its gotten to the point where me and my best friend hang out maybe once a month for a few hours to catch up and thats it(compared to our daily linch breaks together and evening video game sessions). eventually i got sick of this as she never pointed out the somewhat toxic behaviour hes been showing. and my best friend inability to see my point when we discuss this topic, which often leads to her constantly criticising me for ditching her when she always just throws me aside to please him. ive started hanging out with my other friends more as shes always busy with her boyfriend and well simply i dont enjoy hanging out with her anymore as whenever we meet up she just criticises me for being distant, how things have changed and how im never there for her while on the flip side shes always going on about how her boyfriend is the only one who actually cares about her and is the only person who bothers to see her. the thing is shes never really made an effort to reach out to me or anything, often when i reach out to make plans or just ask to play video games she cancels the day before or as im setting up my pc as he usually invites her somewhere more interesting. so we have really drifted. now today shes messaged me basically saying shes done with me, she cant be bothered with me anymore and she said i decided to be distant so shes gonna call the friendship quits as she hates being treated second best. ironic if you ask me. i tried coming to a compromise with her, offering to be there more and make more plans and involving her but she was having non of it. she fully believes her boyfriend is the only person whose ever there for her and that no one else bothers which is just stupid. how am i supposed to help her when she wont hang out with me or respond to my texts? genuinely shes so negative now when talking about me and genuinely thinks hes perfect in any way and will not criticise him. im honestly not sure what to do now because i dont wanna lose my best friend but she cant see the issues with her boyfriend and their relationship while also completely ignores my side and any issues i might have. to be honest im also pretty tired of this but im also aware of the weird behaviour hes showing and dont wanna leave her in a situation which could be very harmful because i do care for her. is there any way i could have handled this better/ can fix it or is the friendship dead?