First of all, so sorry to hear this.

The only advice I would give you is that any event can be framed in your mind any way you want. No doubt this is a crappy thing, but if you can frame it to your kids that it is a "challenge" that you need their help to beat, and "dang it, the cougarmikey family isn't gonna let something like this take us down" it might help. If he sees you deal with huge life problems in this way, might help him be more ready for when something like this happens to him.

I am sure you are struggling as well, who wouldn't? But if you try to frame it in your mind as a challenge to teach your kids how to deal with big emergencies, might help you as well. We only get a few real chances in life to show kids what we are really made of in emergencies, and looks like this is your chance. Good luck and hopefully everything works out for you.