I think men would develop a whole new level of insecurity. They’d be emotionally confused and become engrossed in attributing it to their jobs or the health of their romantic relationships. I imagine something like this, “it’s occured to me because of my heightened emotional state that my feeling for you aren’t what I thought at first and I need to take some time off to assess myself and why I feel about you the way I do…” There would be retreats for men to escape to during their periods, therapists would boon, more men would be getting massages and pampering themselves, children would be expected to walk on eggshells during dad’s special week, how a partner reacts during the man periods would become an issue of irreconcilable differences brought up in divorces, cheating and abuse would be expected to get more leniency. Also, men would get all weird about their physical self images, avoiding their partners and questioning their attractiveness and desires because of smells, goo, bloated bellies and tender breasts.