L, I'm glad you posted. Sorry to hear about the job situation, but day work is far better in the long run. You'll make it. I have faith in you.
As for the children...I'm glad your son is doing okay. Your daughter is my concern, but as long as she's working, she's got an outlet for her frustrations and away from them for a period of time. She's got goals and she'll meet them in time.
Now about, the @ss, his projections are his own view of his life, and of course, he's got to blame someone for his mistakes. Unfortunately, you are the nearest one at hand. As for the credit card debt....anyone should be able to look at the dates of the purchases and know you didn't make them. Keep all of his emails in a safe place and have them ready to pull out if you need them. When he's on such a tirade, just say, I'm very sorry about how you feel. I hope things get better for you and then just drop it. Don't fuel his fire with any comments. The less you say to him, especially in black and white, the better.
Please take care of yourself.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.