Jeff Zucker’s nine-year tenure as president of CNN ended in an abrupt fashion on Feb. 2, days after he acknowledged to company lawyers what had long been rumored in television news circles: He was in a romantic relationship with Allison Gollust, CNN’s executive vice president and chief marketing officer.

Ms. Gollust had worked alongside Mr. Zucker for more than 20 years, starting as a senior publicist at NBC’s “Today” show in 1997, when Mr. Zucker, then in his early 30s, was executive producer. Their relationship is central to Mr. Zucker’s resignation, which was forced by WarnerMedia, CNN’s parent company. WarnerMedia’s standards policy states that personal workplace relationships must be disclosed immediately to “avoid a conflict of interest.”