On Friday, she officially ditched the Democratic Party and announced she has registered as an independent. The move wasn't entirely a shocker, yet it was still a gut punch for Arizonans who worked hard to send a Democrat to Washington.

"Everyday Americans are increasingly left behind by the national parties' rigid partisanship, which has hardened in recent years,'' she wrote in an exclusive column for The Arizona Republic.

She's right about that. A third of Arizona's electorate is registered as independents. Too many people just don't fit inside the "tent" of the Democratic Party or the fragmented Republican Party.

"Pressures in both parties pull leaders to the edges – allowing the loudest, most extreme voices to determine their respective parties' priorities, and expecting the rest of us to fall in line," she continued.

She's right about that, too. The loudest Americans espousing the most extreme views suck all the oxygen in the room, leaving everyone else disenchanted, lost and worried about the future of our country.

Leaving the party is a political move

Sinema doesn't take responsibility for any of that and instead tries to portray herself as the victim of partisan "divisive, negative politics."

Arizonans "are eager for leaders who focus on commonsense solutions rather than party doctrine," she wrote.