On the one hand, the only reason I’m at all surprised by this headline is that I had heard precisely the opposite reason cited for her withdrawal; “big tent” Republicans have sided with Democrats against conservatives at every turn for my entire lifetime. (Christine Todd Whitman, Arnold Schwartzenegger, William Weld, Pete Wilson, Michael Bloomberg, and on and on and on)
On the other hand, “quietly” in this context means that she has done so without any public statements. In other words, the news article cannot back up its own assertions. This is the old “unnamed sources” gambit, and is entirely worthless.
BTW, did anyone see the completely lame columnists. One actually had titles like, “I’m sick and tired of being sick and tired,” “How to... 101” and “The Buck Stops Here.” Biologists have found neurologically impaired shellfish capable of creating more meaningful titles.