Yes you can.
By the way, multiple postings won't get you more or better answers.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
You would be eligible for a divorce here in San Antonio if you have lived in the county for at lease 90 days. You appear to have the 6 months residency in Texas from your posting. An issue to be reviewed is if you and your spouse have any property in Mexico that needs to be addressed.
You have to qualify as a resident of Texas for at least 6 months. Do you file taxes in the US or Mexico? Do you have a valid and current Texas driver's license? If your husband is in agreement to file in Texas, then you shouldn't have any complications but if he chooses to fight you on the residency issue then make sure you can prove you have established a residency in Texas.
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