honestly she might be doing it just to cover the bases if they’re desperate. i don’t think it’s personal or targeted at all, just that if there’s callouts it’s customary to ask around. i see it from both sides, as it’s definitely annoying to keep getting asked to come in, but i’ve been there as a shift and had to ask someone if they could work on their requested days off knowing why they had requested. because you never know, sometimes people say yes anyway. but know that you aren’t required to respond. if saying no is what’s making you feel guilty, you don’t have to say anything at all. you won’t be punished for ignoring a message on your day off, plus that might also make her not text in the future if she knows you won’t even say anything.

Mute your SM's texts, don't respond and if they call, say sorry I am in school/the library/busy with schoolwork, then answer no if asked to come in. Still doesn't get the hint? Put her number on your Do Not Disturb list,and stop answering call and texts when not at work. You can still look at texts to see if it's something important, and ignore if it's not

Had this issue with my old manager. She would ask me to come in while I was at school, and when I told her no, I would find my schedule changed to during school hours. I ended up having to screenshot my hours as soon as they dropped, and putting her on Do Not Disturb while I was off.