Sarah is just pissed at the GOP Establishment, who recruited moderates to run in 2014, who beat Tea Party candidates in the primaries and were elected in the General Election.
The Establishment correctly projected a move to the center would be beneficial in increasing their numbers, this was the opposite direction Palin wanted to go. She's been pissed about this for quite a while.
So she thought she'd post anger on Facebook, put together one of her Mama Grizzly style statements, then leak it to the press. That way her followers would go to her Facebook page and read her profound statement, following that they'y clink on her prominently displayed link to SarahPac. Ching, ching, ching!