cold turkey; to go cold turkey on sg. hirtelen abbahagy, pl. "lejön" a cuccról; megvonásos leszok(tat)ás forrás: Youtube - Emeli Sandé: Here it comes

an about-face, about-facing, do an about-face definíció itt szövegkörnyezetben (ahol ráakadtam):  "But last night on Twitter, after praising a successful Passion Projects event, she unexpectedly did an about-face, confirming she was leaving GitHub at the end of the month..."