The price of the divorce is not affected by the fact your spouse is in prison - although it may be easier to serve her while she is in prison.
You can only get the filing fee waived if you are indigent and don't have the funds.
According to the Pro Se Divorce Guide from the State Bar of Texas, "If you cannot afford the filing fee, you must file an Affidavit of Inability to Pay Court Costs, which you must sign in the presence of a notary public, at the same time you file your Petition. If the Judge accepts your Affidavit of Inability to Pay Court Costs, your filing fee and other court costs will be waived."
There is a site in Texas (www.cheaptxdivorce.com) that can help you prepare the papers for $149. However, you will have to file an affidavit indicating to the court that you cannot afford the filing fees. Good luck to you and God bless you.
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