Just reviewed and remembered you have four young children and a joint business. No way should you be negotiating this with him without legal advice. There’s just far too many things to be considered.
Will one of you buy the other out of the business? Four small children is a lot of child support (and a boatload of childcare expenses if you were to take a job). What about college expenses when the children are older? Is there a family home? Do you have accurate financial records on your business? (Many women have had to get forensic accountants to find where the money is hidden). With four small children, how much of the actual work of the business have you been doing? Does it have resale value?