So sorry to hear about your loss, and trying to keep everything going when you're feeling like you're slipping into a pit.

I was in your shoes a long time back. My second husband committed suicide before Christmas and it was painful for a while. I still have trouble around this time of year.

I would encourage you to stay strong but also to know when enough is enough. Self-care is critical right now, so even if it means missing teaching to recover do it. You can't give from an empty tank, as my t would put it.