Disclaimer: The following is for educational purposes. No review of documents, etc have been done. In essence, it can not be considered a legal opinion.
Community property can be tricky and confusing in Texas. The general rules/presumptions seem quite simple. Anything bought during marriage is presumed to be community property. The presumption can be overcome by a showing of "clear and convicing" evidence (fancy term meaning that the person wanting to show it is their separate property must make a really good factual argument showing that is in fact their separate property). A conveyance from the seller to you as you "sole and separate property" is pretty clear. Anything purchsed before the marriage is considered your separate property.
In Texas, the spouse must consent to placing a lien agains thte homestead. Just by signing on the note, does not necessarily mean that it is part of the community. If the property was bought while married, the presumption remains that it is community property.
I assume you do not have an attorney at this time, but if you do have an attorney addressing your divorce, talk to him/her regarding the facts in your case. Attorneys handling divorce work commonly deal with this issue and it is one which comes up often.
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