In general, your filing status depends on whether you are considered unmarried or married. For federal tax purposes, a marriage means only a legal union between a man and a woman as husband and wife. The word “spouse” means a person of the opposite sex who is a husband or a wife.
You are married and living together as husband and wife.
You are living together in a common law marriage that is recognized in the state where you now live or in the state where the common law marriage began.
You are married and living apart, but not legally separated under a decree of divorce or separate maintenance.
You are separated under an interlocutory (not final) decree of divorce. For purposes of filing a joint return, you are not considered divorced.