I(17M) like my Ex Girlfriend’s Best friend(17F). What should I do? HELP!!!

ok so some context before you guys start assuming things just from the title

before dating my ex girlfriend and i were really really good buddies, she was the first love of my life, and i had confessed my feelings towards her back in April 2021, after this we dated each other for a total of 4 days after which she decided to call it quits because she didn’t feel the same way about me, after that about 10-15 days later she told me that she regretted breaking up, after this the chick told my best bud that she regretted breaking up because she had lost me as a friend and not because she wanted to date me again, after this I decided to keep my distance from her, i did that for 4 months and then one fine day, due to an accidental encounter with her, she told her mom that she wanted to date me, and my mom and her mom are pretty close as they are colleagues in the same school.
her mom told my mom about this and then my ex texted me and we started talking, we were ig in the “talking stage”
after this around September last week she said that she was confused about how she felt about me back in April and had now realised that she had feelings for me aswell, basically she loved me is she what she said, then we decided to get back together, but i made it very clear that i wanted this to be a long term thing as i never saw her as someone who i would just date for the sake of it or date casually, she understood that and then we started dating, things were going very smoothly in the initial 3 months, she and her mom were there for me and my family when we lost my grandmother in December, even though we’ve broken up and it didn’t end well (you’ll get to know why) I’m still very grateful towards her and her mom for being there for us when me and my family needed it the most.

OK….so now comes the “shitty” part of the story…now my ex girlfriend is friends with a guy and they’ve been really good friends for 4-5 years (basically as long as my ex and i had been friends) and she was really fond of him, which i didn’t mind at all, I’m not the type to get jealous and/or insecure from these things, but she was ( more on this in a while)
ok so around April first week she randomly told me that she had caught feelings for her guy best friend but she didn’t want to break up with me,
now, whenever we’ve gone out and the guy friend is present there, i would be the one getting ignored constantly by her and she would always keep on talking about him and every conversation of ours would somehow land on this guy, im actually really good friends with the guy now, but yeahhh, then i told her that it’s better that we end this because i dont her repressing her feelings for him and then start resenting me in the future which would make things toxic between us, so we broke up
after this in school, she told her friend group (who, I’m very good friends with aswell) about our break up, all of them said one thing, and that was that she made it sound like a flex, and i noticed that aswell, anyways due to some more shitty reasons, her entire friend group decided to leave her as she was extremely Manipulative and toxic in nature, now amongst these guys, there’s a girl, that I’ve grown very close with, we text each other daily and we’re both very fond of each other, some peeps have said that she might like me aswell, but I’m not very sure what to do or how to go about this situation.
Plz suggest me what to do
thank you and extremely sorry for wasting your time if i did
have an amazing day ahead 🙂