I know a PP suggested listening to meditation on you tube (sorry I'm not sure who it was) but it might be something to try?
I listen to a guided meditation or an audio book most nights, and they help me get off to sleep.
Just concentrating on the words and letting them flow over you will help quieten the other thoughts that are whirling at the moment.
The next few days aren't going to be easy but rest as much as you can. Write yourself a list of things to do/people to contact, delegate whatever you can. It's okay to take it minute by minute when you need to, but you will make it through.
I've been there, got the T-shirt, be brave even when you feel anything but 💐