If you are married as of the end of the tax year, unless legally separated, then you would have to file married filing jointly or married filing separately.

However, if you have a qualifying dependent, your spouse didn't live with you for at least the last six months of the tax year and you qualify for Head of Household, then you may be able to deem yourself unmarried for tax purposes and file as HOH.  You cannot file as single.

Please refer to the article below for more information on potentially qualifying to be considered unmarried.

https://ttlc.intuit.com/replies/4206137