Since you are married you have two choices for filing - Either married filing separately or married filing jointly. Unfortunately, to file jointly he will have to agree and also sign the return. Another option is if you have not lived together for six months you can file as single. It is not clear from the facts whether this is true.
Any individual seeking legal advice for their own situation should retain their own legal counsel as this response provides information that is general in nature and not specific to any person's unique situation. Circular 230 Disclaimer - Advice given in this response cannot be used to eliminate penalties with the IRS or any other governmental agency.
If you did not live together for the last six months of the year, AND you have a child that you take care of, you are not considered married under Section 7703. If you do not have a child that you take care of, you will be considered married unless you are legally seperated. Married filing seperately is very unfavorable for both taxpayers, but there appears to be no way around it. If you seek legal seperation or divorce, you will be able to file again as single.
You must also have a child. but if you have a child, the basis for claiming Single(Actually Head of Household), is Section 7703(b).
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