Here's a trailer for the Lynda Carter thriller vehicle, Hotline.
I would watch this, however three things jumped out at me while watching this trailer. First, the phrase “crisis worker is being bugged by a crank caller” seems like a weird phrase to use, like he's giving her wet willies instead of harassing her by phone. Second, I somehow immediately identified this as a TV movie. And third, when Carter hits that dude at the end, I'd wager that's where she discovers that her trusted confidant is the killer and makes her escape. Horror 101 peeps!