More on Characters' character

I'm reading a book by an author I've never read before, and the heroine keeps doing stooopid stuff. It's a mystery/thriller and there's a stalker after the heroine. First off, she tears up two disturbing/threatening letters, before she decides to show the third one... to a friend. That's right, not the cops. A friend. The friend is the one who says he'll pass the letter on to connections he has in the police department.

Then when the heroine finds a dismembered body on the private (restricted entrance to those living there) beach and a heart carved in the sand with her name, she says nothing about the heart, because she thinks maybe she imagined it when it's washed away in the tide before the police arrive. Who gives a crap if you imagined it ya stupid beyo*tch! Tell the police and let them decide. You ain't gonna be imagining the world of pain coming down the turnpike of life to run your ass over in the very near future.

She gets another letter, 'hand delivered' this time (no stamp) to her mailbox and takes it with her on vacation. ::slaps forehead:: once she gets around to reading the stalker mail, does she contact police back at home? You don't even need 3 guesses for this one, do you? Or how about the postcard that's sent to where she's vacationing by the stalker--do you think she faxed, phoned, emailed, snail-mailed, telegraphed, morse-coded, text-messaged, or carrier-pigeoned this pertinent piece info to the dectives working on the case? Nope. Blockhead decides to wait till she gets back.

I. Hate. When. Writers. Make. Their. Characters. Do. Stupid. Ass. Things. For. The. Sake. Of. The. Plot.

Your character loses all integrity, viability, and depth. They also lose the readers' respect. Furthermore, the reader stops trusting 'you' the writer. Where you want your reader to follow whichever path you decide to lead them down storywise, you'll have, instead, an unwilling participant, questioning everything you say, do, and present. You never, never, never want these things to happen.

If there's a plot twist that you simply must have in your book, find another way to get there than to make your character a f*ckin' imbecile. Need more story? Make something up. You're a godd*mn writer. Ever heard of 'conflict'? Get you some. Do not reel out the storyline by trying to 'artificially' delay the inevitable with stupid assed dumb decisions and/or actions on the part of your characters.