Okay, Tanya...(just for you there alemana)...I can't speak to your marriage or your experience...but I am a pro/am dancer who dances MUCH more than my husband, but who originally began dancing so that he and I could look decent at social functions.
My first observation is that once I started getting a little good, even though I like to think I was delicate about it, I would get frustrated with his lead/frame or lack thereof...he wouldn't understand why I didn't get something and I became more and more certain that it wasn't my problem...again, trying to be gracious but not really succeeding...
Also I think a part of my learning curve was that as a very aggressive overachiever and as someone who liked how good it was starting to get with my pro, I began "helping" my husband to get better...and as someone who was dancing mostly routines on my lesson time...wherein lead and follow wasn't my primary focus, especially with the pro at the beginning....when I would go back and dance with dh, I continued to focus very little on following. I tended, rather, to focus on things I was working on in my lesson like, MY posture and MY lowering and MY foot pressure and MY balance and the position of MYy head etc...which wasnt a problem in a lesson because anyone can feel my pro's lead and he certainly knows where he's going as well...so consequently with a bit more confidence and knowlege and a lttle less focus on lead and follow as well as becoming more acclimated to my pro than my dh... dancing as a married couple began to be disappointing and not fun for either of us in the way that it once was when neither of us knew a thing.
I think is is understandable for someone to miss that, to want that back. It's sad that we dont know we are going to lose that when we embark upon the road to progress. Still I don't think it has to be a permanent loss, but like all growth we will have to devote more time to dancing as a couple, near to the same amount of time to it as we do to our pro/am dancing or at least as much as possible, or we will have to discuss the loss and find ways that we can dance that will be less frustrating (like just doing set choreography for a while or agreeing on some basic moves to avoid confusion or talking about which scenarios cause the most trouble...and I would reccommend that you do this when you are not dancing and have no intention of dancing...dh and I have chosen saturday mornings as times when we are both rested and can get together over a cup of coffee and discuss stuff while we are not upset over it...in attempts to understand each other better, problem solve...etc ...when everyone is well rested and no one feels threatened...I find it very useful...and lastly, I would make sure that you also do other stuff that is non-dance related before going to dance toether that puts you in a confident state of mind about your relationship before going off to dance...we all get nervous about potential stress and sometimes we can sabotage our efforts before we even start...I like dinner and conversation before dancing and good sex afterward

...just to sort of make the point that while we have room to grow in some areas, we are still very very good in others

and that might be just the sort of reassurance that he is after....
dunno, hope some of this helps...pm if you wanna get specific...hug