Stuart Armstrong
Yes, many times a woman goes by more than one name. Or parts of her full name. Her full name could be Antonia Catalina Avila Cid. But don't jump to that as the only solution. People changed or modified their names often, so that in later records you may not recognize the same person found in earlier records. I have several instances of females having as many as seven different surnames in various records, along with several variations of their given names. Whether it was that they had decided to be known by different names, or that the informants were not well informed, is hard to tell. I can certainly relate to your dilemma trying to decide if the two names belong to the same person.
Name variations seem to be more common with women than men. Perhaps it was because of the culture of the times, that the women were often not present at the christenings of their children, being "churched" or recovering from childbirth, and those present may have known her by her

It's not uncommon for a person to be referred to with two different names.
i.e. Juan Antonio Carlos's parents are Jose Carlos and Maria Carrillo. He can be referred to as either Juan Carlos or Antonio Carrillo. I've seen this many times.

Jose Carlos de Leon

I believe these are two different women-- wives of the same man. I'm sure someone recording the vital information perhaps mixed up the names sometimes, but I don't think there is only one woman. What makes you think so?