Program Etiquette

Unless the girlfriend is a stepmother by legal marriage, she would not be listed as a parent

If they have been together 10+ years I would treat them as married and her as a step parent. And in that case, 'parents of' it's appropriate. Why does it not sit right? You could ask the father of the groom what he would prefer.

Unless you're having a complex ceremony with many elements your guests may be unfamiliar with, you can take the easy way and just skip the programs. Otherwise, I would actually write it as "Mr. John Doe and the late Mrs. Jane Doe" because those are the actual parents. Does he specifically want his dad's girlfriend listed?

If your Fiancé does not view this person as a parent, then I agree “the parents of” wouldn’t be appropriate. I would first see what your FH feels comfortable with, as it’s his family and his wedding. Then you can either just go with whatever he thinks feels right, or he could run his idea by his father (and gf, if he wants to/feels comfortable doing so), to see if he/they feel good about the wording also. Ultimately though, I think your FH’s opinion is the only one that really matters.

Also, you could avoid the situation entirely and just skip doing programs. TBH, they are a waste of money (unless there is a compelling reason to need them, such as an interfaith marriage where guests will need an explanation of what is going on, or if parts of the ceremony will be in a different language, etc.), and most people are skipping them these days.

Mother of Groom:
Mother's name

Father of GroomFather's name and gf's name
I've seen a funeral program listed out like this. A social unit is listed together, the gf does not get her separate designation
OrParents of Groom:Mother's NameFather's Name and Gf's name (or skip gf's nake altogether)
I would NOT list a gf or stepparent as a "parent" and exclude the deceased mother.

Save your money and skip the programs. Everyone tosses them. Our minister even suggested to forego them. It's one less thing to worry about both in time and expense. If you really want programs I would suggest wording it something along these lines:

Father of the Groom: <Father's Name> accompanied by <Father's Girlfriend's Name>

Thank you, all! Your responses are greatly appreciated!