You are entitled to an equitable distribution of all of the assets accumulated during the time of marriage. This more or less means 1/2 of everything. Additionally, with a marriage of this length, you have a good shot at getting permanent alimony. The court may take his infidelity into consideration when determining alimony. You also may be able to have the judge order him to pay your attorney's fees if only he has access to the money. If you would like to discuss this further, feel free to call my office in order to set up a consultation.
The short legal answer is that you are entitled to an equitable distribution of assets accumulated during the course of the marriage. The longer answer includes both issues of law and practical considerations such as whether you and your spouse executed a premarital agreement, whether your residence (and other assets) would be considered marital, the type of business involved and whether it is a viable / going concern, where you and your daughter will reside after the divorce, etc. If you truly want to proceed with a divorce at this time, you should consult with an attorney who can advise you on a course of action that would be best for you and your family.
Unfortunately, most judges won't consider "cheating" a fault for which to punish. In most jurisdictions, a divorce is no different than breaking up a business partnership. Debts and assets are divided. Having a 22 year-old is almost irrelevant because she is considered an adult in the eyes of the law. You should move forward with your plans to "move on." This doesn't sound like a way that you are happy living. Consider this a 50/50 partnership (you helped him at home so he could take care of the business), and find a way to get a fair settlement.
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