Okay, so this has caused me to raise up on my soapbox.
When I was having my hair done last week, my hairdresser (whom I adore and found out is probably moving to a salon that is on my street — who knew?) and I were talking about Ms. Spears and how even the hardest of hearts had to pity her. My hairdresser had been through a messy divorce and had custody issues with her ex and she told me, “No matter what you do, you’re judged. And people immediately apply the label to you that you’re crazy.”
I did not argue with her, because she was obviously coming from a personal and painful place, and I don’t think she’s crazy. And she does some damn fine hair, so far be it from me to piss her off. But honestly, Britney’s been crazy. Dude, she’s attacked cars with umbrellas. And shaved her head on a whim. These are not the actions of sane people who have control. Just not.
And can I just say that this is now the SECOND family she’s broken up? Some women just have this need to be the girl that’s chosen over some other women. Reminder: KFed was a father in another family when he and Brit hooked up, remember? He actually had a baby on the way. And now this?
I remember, when Brit and KFed came out as an item, how horrible I felt for his wife. How mortifying it must be to have your husband and/or father of your children publicly parading with someone who’s not you. And I feel that way again, because damn, it’s not right for any woman to have to go through that.
Men, take care of your bidness at home. THEN go find the crazy whore.
(stepping down off the soapbox)

I don’t like the term “homewrecker”. I just believe that its really hard to wreck a family that isn’t already divided. Not to say that I condone it, but lets be realistic here.
Also, I think the actions you listed were the least of her insanity. She shaved her head because someone threatened to use her hair in a drug screening process. Whether that’s even possible or not, I find it logical that she would shave her head to keep her kids.I find her attacking a car totally legit. Paparazzi are assholes, they say terrible things to get a shot, and after awhile, probably everyone looks like a paparazzi to Brit.
However, having a showdown at her house with the children present and watching is insane. Especially because you would think that if she was willing to threaten someone’s life, she’d at least be willing to show up to a custody hearing.