On Mondays, I answer questions frequently asked by those considering a return to the Catholic Church. How do I know this stuff? I was away for more than 30 years myself, and am the co-author of When They Come Home: Ways to Welcome Returning Catholics, a book for pastors and parish leaders interested in this ministry.
My healthy mother, who hasn’t been inside a Catholic church for even longer than I have, has recently announced she wants a Catholic funeral. I’m not exactly sure what that means, other than a Mass, or how to honor her wishes.
First, I’m glad to hear your mother is making plans while she’s still healthy enough to communicate her wishes. I hope she’s documenting them in some form.
Second, I’d suggest you set up an appointment for the two of you with the funeral ministry at the parish nearest her; this may be called the Bereavement Ministry or the Circle of Caring or something else. The office staff can direct you to the right person. Explain there is no imminent need but that the two of you want to explore what decisions need to be made.
The U.S. Conference of Catholic Bishops’ site is rich with information about bereavements and funerals, so you may want to spend some time there before your appointment.
Finally, I would be remiss in not suggesting to the two of you that if a Catholic funeral is important to her even though neither of you has been to Church in years, this desire may be a stirring of the soul. Consider going to a Mass or two together and talking about why her wish is so important to her… and about your laudable desire to honor that wish.