Covergaard, trust me, I was there throughout my childhood, my mother would do anything (and still would) for attention, including all sorts of nasties to herself without regard to what would happen to us, we ended up in care more times than you've had hot dinners.
Some peple just have no responsibility when it comes to looking after their kids, they don't want to admit they are sick or that they're harming their children, they just do not see it as a problem! In cases such as my own mother's, they often don't learn by it when it backfires either, she has lost her kids, one died as a result and now she cannot have contact with her grandchildren due to her being too much of a nut job, but still she will always maintain she did her best always
it's always the innocent who end up damaged by this, it's just the way it is, you either move on and forget that person exists or you let it eat you alive.