If the pill is not working for her, and her ob-gyn assumes it's her fault and won't look into switching to a different pill, I would suggest that she SWITCH DOCTORS. In retrospect, that was a big warning sign that my previous ob-gyn did not know what she was doing, and if I'd realized at the time that that was not a good sign, I would have spared myself a serious infection that eventually led to a week-long cancer scare.

Women are often brought up to assume that everything's their fault and not to question authority figures, for fear of being labeled neurotic, bitchy, or a Munchausen's patient (in medical situations). I enjoy being submissive in my sexual life, but allowing that attitude to be taken advantage of in a medical case can lead to serious consequences. If her pill isn't regulating her periods, it isn't working properly, and it is her doctor's job to find one that does.

/rant off