I have to say I felt very dangerous after I was certified. Not sure of myself or anything that I learned during class. It took several very shallow quarry dives plus pool work to feel as if I could do this. Like you, I felt I should not have passed, but I did. Had issues in the pool performing the skills, could not figure out how to perform them fast enough before I needed a breath. I would hold my finger up to my inst to let him know I would be right back. I would surface take a breath then come back down to try my skill again. When the time quarry was upon us, I could do them, but not as well as I would have liked to do them. Each piece of it had to be thought out and then done, one section at a time. I am still no where near where I would like to be, but I have not given up. One advantage I had compared to you, is that my husband and I did our courses seperate. I did mine one month ahead of him. This just meant that he could still live without me killing him. However, I did the course with my daughter, if I could do it over, I would do the course myself, with no one there with me. NO one to worry about. Things that I did to attempt to fix my issues is to take some small extra classes, like nav. The one big thing that I did, was go to the quarry with just my daughter and myself, left hubby at home and we just did as we pleased. Stay shallow, just swam, no tasks, just us, looking at the fish and swimming. This one little thing, made me realize I had it in me. It also confirmed that daughter had it in her as well.
I think your comment to your wife about not diving with her will be a hard one to take back. I am sure she is hurt by this comment. This will be a long road to recovery here. One of the other things that I am doing for myself, is taking a class in PA to just work on skills like kicks and boyounany, again, leaving everyone at home. This will just be a me thing.
If I were you I would pick up the cards and just sleep on it for a while.
Now that both husband and myself are certified there is still plenty to disagree about when it comes to diving. Not if we will dive together, but who is right, how far buddies should be from each other, how things are done. Just remember, she is always right, no matter what. Now, if I could only get my husband to internalize this, we would be fine.
Good luck!