i...i don't know

tomorrow would've been my older sister's 21st birthday...she passed away in April and I'm really not looking forward to tomorrow. it hurts so much. i don't know what to do, i have school and i can't not go bc they're strict with how often you don't show up. my SO goes to the same school so I see him first period then lunch so I'll be a bit happier seeing him, but i won't be able to focus whatsoever in my other classes and the teachers push you to work if you don't, they don't let you just relax or anything. i don't want to wind up crying my eyes out in the middle of class or something. again, i can't not go, but if i go I'll feel like shit.