Well you have a really difficult situation
Living with and loving someone with bipolar can be great sometimes and a nightmare sometimes.

I don't want to give you any wrong advice that's why I was hoping you have a therapist or maybe a school counselor. They keep everything confidential unless there's a serious imminent danger.

My dad has passed away, but I remember being a kid and not knowing when he was going to be ticked off, depressed, or the funnest guy ever. Now I'm that mom... I've worked really hard at not having meltdowns in front of my kids, and happy to say it's been over 6 months since I lost my cool in front of them, I wish I could take back the past times that i had.

I guess I'd recomend you have activities that keep you busy and help you feel good about yourself, in addition to as soon as you can get a counselor too.

Hugs