If he filed for divorce and knew where you were located, he should have served you with papers. Otherwise, you would have to find out each county he lived in to review the records in that county. The simpliest way is to find him and ask the question.
In both cases, you can conduct an internet search to determine if there are civil matters in his name, which may include divorces for you and another woman.
Also, a private detective may be able to provide you the information you want.
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