Generally, filing married filing jointly results in the lowest net income tax. If you divorce, you will be required to file as single, or perhaps Head of Household. The total of your tax and your husbands will probably be more than staying married. Also, if you continue to live together under the same roof, the Head of Household filing status will not be available.
I suspect you have received bad advice. Would you really divorce for a few dollars in taxes?
Please keep in mind that there are many variables that could be applied to the brief facts you have given. The information offered here is general in nature and is not a legal opinion nor is it specific tax advice.
In addition to Mr. Lowery's advice, there are a myriad of other considerations - dower and curtsy rights, inheritance, healthcare, as well as a number of others that you may not have thought of.
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