There is no such law in Florida. You need to find out from your husband's employer how they define "dependent" for the purposes of health insurance. Typically, a dependent is a spouse and child(ren) of the employee. Typical documentation required as proof of marriage is a married license. In addition, this requirement of living in the same address seems questionable to me because children who are in college, living away from their parents, are still considered "dependents" up to a certain age. To that end, living in the same address as a requirement to eligibility for employer-sponsored group health plan is highly questionable.
Employers and group health insurers can change benefits under a group health plan with proper notice, as long as these changes are applied uniformly to similarly situated persons covered under the health plan. Under federal rules, “proper notice” is given if employees are notified about the health benefits change within 60 days following the change.
In response to your health insurance question...What are your husband's obligations to carry/pay for your insurance?
From your note, it sounds like you get employer-sponsored insurance as a dependent through your husband's employer. A "dependent" generally means spouse and children. Upon divorce, you will no longer be a "spouse" so you will lose the "dependent" status and will no longer qualify for your ex-husband's group health plan. You will, however, have an opportunity to continue in the same group plan for 36 months through COBRA (if COBRA is not available based on the size of your husband's employer, then FL continuation coverage for 18 months). Downside is that you will have to pay 100% of the premium plus 2% administration fee. This is likely to be cost-prohibitive.
Your husband could also chose to drop you from his employer-sponsored insurance without telling you (prior to the divorce). However, the employer is required to send you notice of your COBRA or FL continuation rights (as described above). Again, you will have to pay for the full premium out-of-pocket.
I hope this answers your question.