I have long held this theory, but recently decided to blog. 
SO, why do we have pain, feel terrible and can't be reasoned with, just before or during the bleeding part of our cycle??
Well the bleeding part can be learnt in numerous publications. As for the feeling like crap, intolerance, lack of reason, bloody mindedness and just feeling terrible: No it's not just because we have a tampon inside us blocking the flow and swelling up, or because we have blood leaking out of us filling a pad and feeling pretty disgusting . IT'S BECAUSE WE NEED IT. We tolerate and cope and settle for some pretty sh*tty treatment because it keeps the peace, so on a sliding scale things are getting worse, for three weeks it's sliding we feel bad, we're upset, we tell our girls all about it, but go home and be pleasant. THEN week four arrives, THAT'S IT, You should treat me well and set a good example of how the kids should treat me, you can cook or do the dishes occasionally. the kids can clean up after themselves, eat what's healthy without whingeing AND YOU CAN TELL THEM ALL THAT, BECAUSE I DESERVE YOU TO DO THAT!!!! Not to say it's mummies time of the month, it'll all be better next week, but to say mummy put's up with being our slave and being treated a way that Amnesty International would object to, most of the time, so let's just pick up our game and treat her the way she treats us. With nurturing care.
If all that happened we wouldn't need to feel that way again!!! I know right??
BUT I Survived It All, and live to tell the tale.
Mojo