There are perfectly acceptable times to trash your ex. Case in point: every woman understood when Jen Aniston accused ex-husband Brad Pitt of lacking a sensitivity chip, after he dumped her for Angelina.
She was justified in letting the public know the depths of her disgust. We sympathized.
If Mary Louise Parker had called boyfriend of seven years, Billy Crudup, a cad when he ditched her for the younger Claire Danes, when she was seven months pregnant, no woman would have blamed her.
Every woman who has been through high school knows that trashing your ex to your friends is not only socially acceptable but part of the post-breakup recovery process, accompanied by a pint of Ben and Jerry's.
Nevertheless, the Palin women take public trashing to a whole new and totally uncool level.
Bristol Palin, 
18, and her baby daddy and former fiancé Levi Johnston, 19, have now publicly announced the end of their engagement and their split. Both have now released statements that the decision is mutual...blah blah blah!
However, the statement only came after Johnston's sister Mercede spilled to Star magazine what is probably the non-publicist approved truth of the situation.
Mercede says Bristol broke up with Levi and doesn't allow him to bring baby Tripp to his family's house because she doesn't want him around "white trash."
Could it be that Bristol is concerned with her baby associating with her paternal grandmother Sherry Johnston, who has been charged with possession and distribution of the drug OxyContin?
Mercede also charges that Levi tried to visit two month-old Tripp every single day, but "Bristol makes it nearly impossible."
Now, the reason I don't doubt Mercede's version of the story -- Bristol trashing her ex and his family -- is because of the very public trashing and more, that her mom has been tied to, which also involves an ex-in-law: Sarah's brother-in-law.
Palin's sister, Molly McCann, split from her state trooper husband, Mike Wooten, and what happened subsequently got heavy coverage during the presidential campaign last fall.
A special investigator, Stephen Branchflower, reported to the Alaska Legislative Council that he had found that Governor Palin had "wrongfully permitted [her husband] Todd Palin to use the governor's office...to continue to contact subordinate state employees in an effort to find some way to get Trooper Wooten fired."
Whew! Talk about an "ex hunt." That takes trashing to a whole new level.
You better not mess with those Palin women when romance goes awry. Slicing and dicing exes appears to be in the family genes.
And the fact that kids end up in the middle doesn't seem to be a concern. Poor little Tripp may never get to know his dad, and Sarah's sister Molly was so slammed by divorce Judge John Suddock that he warned her and her family to stop "disparaging" Wooten's reputation or risk losing custody of her kids.
It sure is ironic. When it was politically expedient, Sarah spruced up her daughter's 
"redneck" boyfriend, and dressed him out of her family's $150,000 wardrobe budget, so he would be presentable at the Republican National Convention. He even got the John McCain bear hug.
Back then, the couple vowed there would be wedding bells. Well, thank God, the McCain-Palin ticket didn't win the White House. No doubt, there WOULD have been a wedding for PR purposes, followed by a miserable marriage for the two teen parents.
Now the Johnston family may be furious about the Palin women diss, but they should take comfort in the fact that Bristol has also trashed her mom's policy of abstinence-only sex education.
Well, duh?
For more on the Palin women, follow Bonnie on Twitter at twitter.com/bonniefuller.