At the end of the day, we have very little to no idea just who Britney really is, or how she deals with her problems. I have always been ultra wary of falling for anything that the media 'trains' me to believe. How much of it is myth, how much of it legit? I don't know, I just get the feeling that somebody (paps, etc) prospers very well from propagating this crap - and the masses just lap it up.
I have never been a fan, but I tend to see Britney as a victim of our age, the poster child for success gone bad - regardless how many millions she has. Unlike many of her contemporaries, she doesn't seem to want to cultivate any particular image of herself. She never seems desperate for attention, certainly not in the same manner as many other celebs. I guess I just have this weird sort of sympathy for her, or at least for the projection we see of her in the press.
And as for the allegations, don't forget that many seemingly stable and upright members of society abuse children - which reflects, sadly, how few of them are actually brought to justice.