WB, I am going to go out on a limb here and propose that her changes are from the increased lovemaking, as well. This was one of the things that surprised my H the very most about resurrecting our sex life. He was genuinely surprised at how much happier he feels, the ease with which he is able to deal with stressors that at one time would have sent him over the edge. He can't believe the way he used to act. Just taking the physical edge off and whatever else happens, chemically, in a human beings' body when you ML benefits both people--regardless of whose idea it was to do it in the first place.
When he said that I wanted to say, Well what did ya think would happen??!? But I didn't. I just said, Yeah it's really great how well designed the system is!
There also has to be a certain amount of mental satisfaction in knowing that she is making her husband happy and satisfying him, instead of being a complete failure in this one area of being a wife. I can't imagine what a number that would do to a person--to know, without a shadow of a doubt, that they were sexual failures. It certainly wouldn't motivate them to jump right in and rectify things.
Glad to hear that things continue to go well. Sorry I did not respond to your earlier question; I couldn't think of anything intelligent to say so I said nothing.