As much as I love to say that both should love each other equally, I believe it should be the man who should love more.
Due to the maternal instinct of a woman, even if they no longer love their husband most if not all women will try to hold on to the relationship to make the family intact. Same can not be said for men as they think more logically than base their decisions on emotions. If a man feels that the relationship is not working anymore and the family is much better without him, he will definite gave up and leave.