There is nothing you can do about him or what he does. If he's angry, remove yourself and go out. Doesn't matter where. If he rants at you. tell him you'll talk with him later when things cool down.
I know you're panic. When my H left, I had a business that was in the tank (I closed it), no degree and two D's. I got a part-time job asap (that was all I could find at first) and then I did temp work (for 1 1/2 years in the same position) before I was hired as a regular. One of my D's went into crisis. I still don't have a degree and I take classes as I can. The job isn't great, but I'm working things the best I can. And, one wouldn't use "spring chicken" to describe me.
The best thing you can do is work on you. Do you have any goals set for yourself? Somedays, my goal was getting out of bed, so, I know where you are.
So, now that we know where you are, where do you want to be? Who do you want to be? Tell me the best things about you...