You are so fortunate that Texas has placed marriages and divorces on-line. You should check with the court clerk on line in the county to locate the date of your husband's first marriage - if you know the approximate year of marriage - and then follow through. I located a spouse of a client of mine in New Jersey using the on-line services in Texas.
Hope this is helpful.
You don't have to prove anything. Just file the petition to declare marriage void and cite as your reason that your "husband" is still married to his first wife. Let him prove that he is not. It sounds like a little backwards to have the burden of proof placed on him, but you can't prove the he never got divorced. You can't prove a negative. Only he can prove that he DID get divorced.
You should consult with a local family law attorney. Trying to do this on your own is dicey and probably won't work. An annulment is not a very expensive proceeding.
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