In 1986 my X husband was sued and charged with fraud. The creditor was granted a judgment of $800,000. They never collected, as we had no assets.

Years later, we started making money, and my husband has his attorney draw up an irrevocable trust. He told me it would protect our assets as we acquired them, and that I would be the trustee, overseeing it all. His attorney drew it up, and we opened a checking acount in the name of the trust. Except for that account, the trust was non-existant. We purchased a home, and it was placed into the trust, for a time. It was removed for refinance purposes, but never put back.

Fast forward to a divorce. Husband hires a trust attorney to claim I STOLE money from the trust, because everyhting that went in was trust money, and everything that went out (all our expenses, mortgage payments, life expenses) was money I stole.

The probate judge says I have lost my community property. How can I claim undue influence? I didn't know I was giving up my community property

I hope you aren't trying to handle this without a lawyer. You are in a community property state?
It would seem to me that your claim is based as much on records proving that expenses were for both of you, proving you didn't spend money on yourself, as it would be for undue influence. (And he never sued you for fiduciary irresponsibility when you were trustee.) There is NO WAY you can do this without a lawyer. Sounds like a very crafty ex.

From the start here the trust was a fraudulent way of avoiding a valid date. And you were a party to that so your hands are not clean here. I doubt if you can claim undue influence because of that. From what you just told us you were aware of the purpose of the trust.

As Joy has said, there is really little we can do to advise you. You NEED an attorney to wade through this mess.