An Annulment of marriage is an order of a court that sets aside the purported marriage of the parties and returns them to a status as though they had never been married to each other. The rules governing Annulments of marriages of persons under the age of 18 are different and broader than those governing adults.
The underlying concept of an Annulment is that for some reason one of the parties did not voluntarily give his or her informed consent to the marriage.
A Texas court can grant an Annulment in the case of two adults if one or both of the parties were under the influence of alcohol or drugs at the time of the marriage, if there has been concealed impotency, if there has been fraud, duress, or force used in obtaining the consent of a party to the marriage, and for a few other more obscure reasons.
If the parties cohabitate after the time the "innocent" party learns about the matter concealed or is otherwise free from the disability, an Annulment will likely be unavailable, and the party seeking an end to the marriage will have to seek a divorce rather than an Annulment.
Competent legal counsel is essential in order to determine your rights if you are considering seeking an Annulment or defending yourself in an Annulment action.