Determining your business's value can make it much easier when you go through a divorce. Your business' value can play into the kind of assets you split and how they're split, so knowing the value is actually great leverage to have.
When you run a business, you likely appreciate having your business for the income stream it creates. Now that you're going through a divorce, your valuation can help you decide how to either split the business or what to split in order to keep your business separate. You need to define what your business is actually worth to do this accurately.