Can only talk for my experience but I will say this...
My wife and I are 2 different persons in the productivity/organization aspects, as I am going to try to explain and hopefully you will get an Idea.
1.- My wife can work 18-20 hours a day, take a shower, sleep 3 hours and go back to work for another 18-20. My capacity is 10-12, after that I am useless. Because of this I need a system that allows me to be as effective as possible, because when I hit the NO_MORE point, it is over. Because of that I use extensively GTD, she do not used, and it is not interested because her list of Blah (when she made it) it is more than enough.
2.- Are you a round GTD? My wife is super efficient at work, but when personal shows up. Me instead are a round up GTD, there is little or no difference between Personal and Professional, and that frustrates her, because I can do more in were she see (our house and personal life)
3.- I need to agree with the expectancies. When I start on GTD (and yes I posted the same question some time ago) I want her to jump in the wagon, and I cannot understand why she resisted so much. The reason was expectancies, when I am organized I am super productive... she is super productive now without any organization (and she does not know she can be even more, but that is another story). Also I want her to do GTD, as much as I like GTD, and as much as I fight everyday to be a black belt, I try to sell and make her another GTD person. GTD it is a personal journey, you can only bring your internal team. Today, when I want her to do something as clearly ask: Can you do this... and I understand that will take sometimes longer that what will take me, but I have learn to trust that she will finish it. (And of course I tracked on my Agendas, but try not to mention to her)
4.- Do not sell the tools, just used. At the beginning I try to sell GTD to my wife, the tools, the palm, outlook, my lists, I was willing to share everything (or more pushing everything on my system on hers) When I stop selling the tools, and just making those my tools, she just got used to my lists, my need to write everything down, my Moleskine and my need to use the note taker wallet at dinners.
After I stop pushing GTD, she was more open to the issues, I have almost 3 years doing GTD, and she do not do it, but she has learn the advantages of some of the things... and in her way and unique style is looking for a way to get to that space.
Also remember something, in my case before GTD I was a complete mess, to-do list that never got done, projects at home that I never accomplish, oil changes more than overdue, has taking me more than 2 years for my wife to see that this is a permanent change, before that, was just the new idea for organization (and I have a closet full of those)
To give you hope; I will share something else. She has an important business trip this week, after almost 3 years laughing to my travel list, she asks for a copy. 2 hours later she calls me and informs me that my list was not complete, since the list did not have creams, cosmetics and other things... I just smile, get my list, got a copy, put her name add these things and print her new copy.
This is the closest she has been to GTD in 3 years, I have hope...
Just remember, GTD is a Journey that you can only do with your internal committee, no one else will join you...
Smile and enjoy the ride...