You can file HOH if you meet the following criteria to be considered "not married" even if you are married:
Married individuals considered unmarried. A married individ-
ual can be considered unmarried for HOH filing status purposes
if all the following apply.
• The taxpayer lived apart from his or her spouse for the last six
months of the year. Temporary absences for special circumstances,
such as for business, medical care, school, or military service,
count as time lived in the home.
• The taxpayer does not file a joint return with his or her spouse.
• The taxpayer paid over half the cost of keeping up the home
during the year.
• The taxpayer’s home was the main home of the taxpayer’s child,
stepchild, or foster child for more than half the year.
• The taxpayer claims this child as a dependent, or the child’s
noncustodial parent claims him or her as a dependent under
the rules for children of divorced or separated parents.