Pascale, I think you are on to something with the menopause/andropause thing.
I remember going through the "baby blues", it was crazy. The advantage was, I had read all the baby books and knew what was happening. Even though I knew, it was just plain weird, my emotions were all over the place and I couldn't control it. Luckily it was mild and it went away in a few weeks.
Women tend to be more "in tune" with their bodies, we are more likely to talk to other women about "hormonal/emotional issues" but not all do. Maybe that's why more men seem to go through MLC. No guy is going to tell another guy that he is feeling "sad and don't know why" and maybe some women (like your wife) is just more hormonal than she is use to being and doesn't feel comfortable talking to somebody. I'm just the type of person that will get a hot flash in a room full of strangers and say something like, "hey, don't worry about my face turning purple it's just another egg dying", but that's me.
It sucks that they get to the point that they take their anger out on the people that love them the most. My husband is close to a vanisher so I can only hope that his anger is now turning on to the girl. At some point, hopefully, they will even out and realize the issue was inside them the whole time. Maybe that is what is really happening when we hear that they "come out of the fog".