I would say, it is a good thing the DM was aware of what is going on. It is a bad thing that your wife was not. Also you should have helped her out before the DM even noticed.

My wife and I dive together all of the time and we both keep an eye on each other. Now we have been diving together for a good number of dives, and for sure things have become easier and smoother for the both of us as it will for you.

The one thing I should stress is don't rely on the DM for anything. I don't know where you are diving, but the DM will not be with you underwater in all places. In many parts of the world (and country) the DM stays on the boat and does the dive breafings and head counds, so make sure you both become self sufficient.

Ace