I've seen and experienced myself how much a woman's sex drive will increase when she isn't spending ALL her energy taking care of a house and children by herself. When the kids are in bed and the laundry is folded, its all some women can do to make it to their own beds before passing out for some MUCH NEEDED rest. Especially when those women work fulltime jobs as well. With a little help around the house, and some extra energy to expend, a woman can blossom into a sexual being.
Not sure if this could be the issue here or not, but thought it rang true with why some women are "just not in the mood" more often than their partners. Myself included at times!

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