The general rule is that if you did not reaffirm the debt while you were in the bankruptcy that the debt was discharged. There are also court holdings in my jurisdiction that if a reaffirmation did not occur while you were in bankruptcy that nothing that you do or sign after the bankruptcy can be considered a reaffirmation. Either the reaff occurs while your bankruptcy is pending or it doesn't happen at all.
But, a consultation with a TX attorney familiar with the local rules and practices will be the best way for you to know for sure.
I hope you found this response to be of assistance.
This response shall not be considered the rendering of legal advise but instead a general response to a general question. While Avvo is a wonderful resource, nothing can be a substitute for an in-depth consultation with an attorney in the jurisdiction in which the law is to be applied. This response shall not be deemed to create an attorney-client relationship, nor shall it create an obligation on the part of the attorney to respond to further inquiry from the questioner.
You are never required to reaffirm a mortgage after Chapter 13 bankruptcy because 1) state law will still require the mortgage company to foreclose if you stop making payments and 2) after Chapter 13, you have brought all your mortgage arrearages back into current status.
So if you should have the house go into foreclosure, the bankruptcy discharge will protect you from any deficiency.