Vertigo, or dizziness, usually results from a disorder in the peripheral vestibular system (i.e., structures of the inner ear). Dizziness also may occur as a result of a disorder in the central vestibular system (i.e., vestibular nerve, brainstem, and cerebellum).
Your husband may also be trying to hide his true income to help him obtain a lower child support and an alimony award. It is your responsibility and of your lawyer to try to uncover any hidden monies, and to prove the actual amount of money that your husband is truly earning.
Talking to a spouse, who is already cheating, only makes it more difficult to actually discover the truth (see how to catch a cheating spouse). And while there are many options available when it comes to catching a husband or wife (see detecting infidelity), hiring a private investigator is by far the most effective way of doing so.