I am so sorry to read that this happened to your hubby, Shelley.

We had a similar situation years ago, and it was stressful for my husband too.

I am sending all the strength I have at the moment for him!

I hope your husband can weather this, without quitting.
I know it is stressful and hard.

It seems the extremity of the abuse is in a small way pointing to a solution of sorts. When bosses of this type blow up, it is because of THEIR own short comings, and character flaws, not the recipients'. When they blow up like this they are creating issues in the recipients to make them feel like a small child, and pushing those buttons is what creates the pain, IMO.
Then feeling "trapped" by the feelings in the present situation then escalates this pain. The boss is in effect dumping his crap on your husband.

I would urge you to listen to your husband and point out that now is the time to START to look for another job. But not to quit in reaction, and thereby put your whole life in chaos. This is what his boss enjoys, sadistic results! If this bully intended to fire your husband, he would have. Instead he is using him as a punching bag.

When I was recovering from my abusive childhood, back in my 20's I had a great therapist who encouraged me to stop reacting and begin to act when confronted with situations. I had learned to react to survive, but as an adult did not learn ways to ACT to solve my feelings. Conscientious sensitive people tend to react most of the time to keep the peace.

Somewhere in this horrible event, there will be some action in the future your husband can begin to do, that will change things for him and you. Maybe find another job on your husband's terms, or deal with the sadistic boss in a different way. But those solutions take time to find and effect.

These are bad times to quit a job..so I am sending you positive thoughts so you can support your husband as he needs, and to also find ways to soon solve this painful problem.