If you will be divorced on the last day of the year - for tax purposes you will be considered as single for the whole year - that means you will file your tax return as single.
However - - because you are living in Texas - which is a community property state - a spouse's wages, earnings, and net profits from a sole proprietorship are community income and must be evenly split - for the time you was married.
If your domicile is in a community property state during any part of your tax year, you may have community income. Your state law determines whether your income is separate or community income. If you and your spouse file separate returns, you must report half of any income described by state law as community income and all of your separate income, and your spouse must report the other half of any community income plus all of his or her separate income. Each of you can claim credit for half the income tax withheld from community income.
If you are married at any time during the calendar year, special rules apply for reporting certain community income. You must meet all the following conditions for these special rules to apply.
You and your spouse lived apart all year.
You and your spouse did not file a joint return for a tax year beginning or ending in the calendar year.
You and/or your spouse had earned income for the calendar year that is community income.
You and your spouse have not transferred, directly or indirectly, any of the earned income in (3) between yourselves before the end of the year. Do not take into account transfers satisfying child support obligations or transfers of very small amounts or value.
Please see more information in IRS publication 504 page 21 - Community Property
Let me know if you need any help.