It's been nine years since The Real Housewives of New York City premiered, and seven years since the most epic, longest-standing feud in the series' history: Bethenny Frankel vs. Jill Zarin. What drove the former best friends apart was never entirely clear. Zarin was supposedly peeved Frankel left for her own spin-off, and that she didn't call her when Zarin's husband got cancer. Insults and gossip were blown out of proportion, and the split became an irreparable chasm when Zarin surprised everyone on Scary Island in season three. The two have traded slights over the years, but don't really talk candidly about that part of their past.