It is possible for a spouse to hide assets. However, most people do not have the means, the time or the dedication to do so. In today’s world, there is a paper trail created by virtually every financial transaction. Therefore, it is generally possible to figure out what money has come into a spouse’s hands and where it has gone.
Generally there will be an order entered requiring both parties to prepare sworn inventories that list all assets and debts. That information will give you a good idea whether your spouse is being honest or deceitful.
To double check, apply the IRS’ “standard of living” audit to your financial facts. Your lawyer can tell you how to do it.