You are now seeing one of the perils of handling a complicated divorce on your own.
If the divorce decree required him to pay you and he did not, you can seek court enforcement of the order. However, if you failed to request division of the property and the divorce is final and the decree does not specify that you should receive half, you may be out of luck.
You should have your papers reviewed by a local divorce lawyer who can advise you whether you have any chance of recovering the money.
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