If no joint income filings (Form 1040), then you are not responsible.
If the business tax delinquencies are payroll taxes (Form 941) and you participated in the business, then it is possible that you could be assessed the trust fund recovery penalty if you meet the definition of Responsible Person. A TFRP assessment results in personal liability regardless of the type of business entity (corporation, LLC, etc.).
Not unless you filed jointly.
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