Probably not, given your living situation.. The IRS spells out the HoH advantages and requirements in Pub 504 (I've added emphasis on the 3rd bullet point to the "Considered unmarried" definition):
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You are unmarried or “considered unmarried” on the last day of the year.
You paid more than half the cost of keeping up a home for the year.
A “qualifying person” lived with you in the home for more than half the year (except for temporary absences, such as school). However, if the “qualifying person” is your dependent parent, he or she doesn’t have to live with you. See Special rule for parent , later, under Qualifying person.
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Did you live together at any time during the last six months of the year?
Probably not, given your living situation.. The IRS spells out the HoH advantages and requirements in Pub 504 (I've added emphasis on the 3rd bullet point to the "Considered unmarried" definition):
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You are unmarried or “considered unmarried” on the last day of the year.
You paid more than half the cost of keeping up a home for the year.
A “qualifying person” lived with you in the home for more than half the year (except for temporary absences, such as school). However, if the “qualifying person” is your dependent parent, he or she doesn’t have to live with you. See Special rule for parent , later, under Qualifying person.
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If you can't afford to live separate, you probably can't afford to file anyway other than Married Filing Jointly. You can use this tool to compare the results of filing different ways: <a rel="nofollow" target="_blank" href="https://turbotax.intuit.com/tax-tools/calculators/taxcaster/?s=1">https://turbotax.intuit.com/tax-tools/calculators/taxcaster/?s=1</a>