Is my bff trying to stop being friends?

We hung out a lot in july and facetimed nearly every night. Now all of a sudden she just stops reaching out to me and stuff. I ask her to hang out, she's busy. I ask her if she wants to ft, she says she's busy. Busy this, busy that, but busy with what? She said 'homework i didn't finish' even though our school never did stuff like that where you had to finish work in the summer. At one point i asked 'hey wanna hang this week?' and she said she was busy with school (again), and the next day she had other friends over.

i hope it doesn't sound it, but i'm not jealous by any means. I only asked her if she wanted to hang out like 2-3 times over the course of the whole month of august. I asked one of our mutual friends if she knows anything abt if she's mad at me, and she said that my 'bff' thought i hated her, but the only reasons she had is bc we didn't invite her to play minecraft at 3am (the only time we play). Point a: we used to invite her all the time, and she'd either say she was busy or just never reply. Point b: she goes to sleep at like 9pm. And i get it like if she felt hurt by that, but she could've tried at least talking to me about it; that's no reason for her to just straight up ghost me specifically. I just don't understand why she's doing this

i keep racking my brain over why, was it because i missed a facetime call? I can't think of anything else and i'm really confused, i just want things to go back to the way they were.

It's obvious that she's trying to end the friendship as diplomatically as possible. Usually people do this to avoid a confrontation wherein they're honest about it. But if you two are homework age she just may not have the social confidence to do that yet. At any rate, this situation seems blatant to me so I don't see why you can't take her (very strong) hints and retreat. She's done with you.