This part of your post causes concern in my mind. In your early 30s and only being married for 5 years you should still be on your honeymoon.
As others have said take it slow and have good communication. Find out what makes her happy while at the same time is something that you enjoy. A D/s relationship isn't always about sex so if that is what you are striving for (a way to spice up your sex life) you may once again become "stalled" unless it is is just based around bedroom activities. But then is is really a D/s relationship since it is just to spice up your "stalled" sex life? Since everyone is different I guess it could be considered a D/s one. I do believe though that you can have a D/s relationship on a part-time basis if that is what you both want.
Hopefully your relationship is still based on a great love for each other because I believe any real life D/s where the partners are living together must have love as a basis to start from.
I imagine many will disagree with me but this is my opinion. Good luck